Class 10

A train travels at a certain average speed for a distanced of 54 \mathrm{~km} and then travels a distance of 63 \mathrm{km} at an average speed of 6 \mathrm{~km} / \mathrm{hr} more than the first speed. If it takes 3 hours to complete the total journey, what is its first speed?

Let the first speed of the train be $x \mathrm{~km} / \mathrm{h}$. Time taken to cover $54 \mathrm{~km}=\frac{54}{x} h .$ New speed of the train $=(x+6) \mathrm{km} / \mathrm{h}$ $\therefore$ Time...

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In an examination, the number of those who passed and the number of those who failed were in the ratio of

    \[3:1\]

. Had

    \[8\]

more appeared, and

    \[6\]

less passed, the ratio of passed to failures would have been

    \[2:1\]

. Find the number of candidates who appeared.

Consider the number of passed = \[3x\] Number of failed = x So the total candidates appeared = \[3x\text{ }+\text{ }x\text{ }=\text{ }4x\] In the second case Number of candidates appeared =...

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(i) The monthly pocket money of Ravi and Sanjeev are in the ratio

    \[5:7\]

. Their expenditures are in the ratio

    \[3:5\]

. If each saves Rs

    \[80\]

per month, find their monthly pocket money. (ii) In class X of a school, the ratio of the number of boys to that of the girls is

    \[4:3\]

. If there were

    \[20\]

more boys and

    \[12\]

less girls, then the ratio would have been

    \[2:1\]

. How many students were there in the class?

(i) Consider the monthly pocket money of Ravi and Sanjeev as \[5x\] and \[7x\] Their expenditure is \[3y\] and \[5y\] respectively. \[5x\text{ }\text{ }3y\text{ }=\text{ }80\] …… (1) \[7x\text{...

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(i) In a mixture of

    \[45\]

litres, the ratio of milk to water is

    \[13:2\]

. How much water must be added to this mixture to make the ratio of milk to water as

    \[3:1\]

? (ii) The ratio of the number of boys to the numbers of girls in a school of

    \[560\]

pupils is

    \[5:3\]

. If

    \[10\]

new boys are admitted, find how many new girls may be admitted so that the ratio of the number of boys to the number of girls may change to

    \[3:2\]

.

(i) It is given that Mixture of milk to water = \[45\] litres Ratio of milk to water = \[13:2\] Sum of ratio = \[13\text{ }+\text{ }2\text{ }=\text{ }15\] Here the quantity of milk = \[\left(...

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(i) A certain sum was divided among A, B and C in the ratio

    \[7:5:4\]

. If B got Rs

    \[500\]

more than C, find the total sum divided. (ii) In a business, A invests Rs

    \[50000\]

for

    \[6\]

months, B Rs

    \[60000\]

for

    \[4\]

months and C Rs

    \[80000\]

for

    \[5\]

months. If they together earn Rs

    \[18800\]

find the share of each.

(i) It is given that Ratio between A, B and C = \[7:\text{ }5:\text{ }4\] Consider A share = \[7x\] B share = \[5x\] C share = \[4x\] So the total sum =\[~7x\text{ }+\text{ }5x\text{ }+\text{...

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(i) A woman reduces her weight in the ratio

    \[7:5\]

. What does her weight become if originally it was

    \[91\]

kg. (ii) A school collected Rs 2100 for charity. It was decided to divide the money between an orphanage and a blind school in the ratio of 3: 4. How much money did each receive?

(i) Ratio of original and reduced weight of woman = \[7:5\] Consider original weight = \[7x\] Reduced weight = \[5x\] Here original weight = \[91\]  kg So the reduced weight = \[~\left( 91\text{...

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(i) Find two numbers in the ratio of

    \[\mathbf{8}:\text{ }\mathbf{7}\]

such that when each is decreased by

    \[\mathbf{12}\text{ }{\scriptscriptstyle 1\!/\!{ }_2}\]

, they are in the ratio

    \[\mathbf{11}:\text{ }\mathbf{9}\]

. (ii) The income of a man is increased in the ratio of

    \[\mathbf{10}:\text{ }\mathbf{11}\]

. If the increase in his income is Rs

    \[\mathbf{600}\]

per month, find his new income.

(i) Ratio = \[\mathbf{8}:\text{ }\mathbf{7}\] Consider the numbers as \[8x\] and \[7x\] Using the condition \[\left[ 8x\text{ }\text{ }25/2 \right]/\text{ }\left[ 7x\text{ }\text{ }25/2...

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Two straight lines PQ and PK cross each other at P at an angle of 750. S is a stone on the road PQ, 800 m from P towards Q. By drawing a figure to scale 1 cm = 100 m, locate the position of a flagstaff X, which is equidistant from P and S, and is also equidistant from the road.

We know that \[\begin{array}{*{35}{l}} 1\text{ }cm\text{ }=\text{ }100\text{ }cm  \\ 800\text{ }m\text{ }=\text{ }8\text{ }cm  \\ \end{array}\] Following are the steps of Construction: (i) Construct...

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Draw a line segment AB of length 12 cm. Mark M, the mid-point of AB. Draw and describe the locus of a point which is (i) at a distance of 3 cm from AB. (ii) at a distance of 5 cm from the point M. Mark the points P, Q, R, S which satisfy both the above conditions. What kind of quadrilateral is PQRS? Compute the area of the quadrilateral PQRS.

Following are the steps of Construction: (i) Construct a line AB = 12 cm. (ii) Take M as the midpoint of line AB. (iii) Construct straight lines CD and EF which is parallel to AB at 3 cm distance....

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Ruler and compasses only may be used in this question. All construction lines and arcs must be clearly shown and be of sufficient length and clarity to permit assessment. (i) Construct a triangle ABC, in which BC = 6 cm, AB = 9 cm and ∠ABC = 600. (ii) Construct the locus of all points, inside Δ ABC, which are equidistant from B and C.(iii) Construct the locus of the vertices of the triangle with BC as base, which are equal in area to Δ ABC. (iv) Mark the point Q, in your construction, which would make Δ QBC equal in area to Δ ABC and isosceles. (v) Measure and record the length of CQ.

Following are the steps of Construction: (i) Construct \[AB\text{ }=\text{ }9\text{ }cm\] (ii) At the point B construct an angle of 600 and cut off \[BC\text{ }=\text{ }6\text{ }cm.\] (iii) Now join...

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Use ruler and compasses only for this question. Draw a circle of radius 4 cm and mark two chords AB and AC of the circle of length 6 cm and 5 cm respectively. (i) Construct the locus of points, inside the circle, that are equidistant from A and C. Prove your construction. (ii) Construct the locus of points, inside the circle, that are equidistant from AB and AC.

Following are the steps of Construction: (i) Taking O as centre and 4 cm radius construct a circle. (ii) Mark a point A on this circle. (iii) Taking A and centre and 6 cm radius construct an arc...

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While boarding an aeroplane, a passengers got hurt. The pilot showing promptness and concern, made arrangements to hospitalize the injured and so the plane started late by 30 minutes. To reach the destination, 1500 \mathrm{~km} away, in time, the pilot increased the speed by 100 \mathrm{~km} / hour. Find the original speed of the plane. Do you appreciate the values shown by the pilot, namely promptness in providing help to the injured and his efforts to reach in time?

Let the original speed of the plane be $x \mathrm{~km} / \mathrm{h}$. $\therefore$ Actual speed of the plane $=(x+100) \mathrm{km} / \mathrm{h}$ Distance of the journey $=1500 \mathrm{~km}$ Time...

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Without using set-squares or protractor construct: (i) Triangle ABC, in which AB = 5.5 cm, BC = 3.2 cm and CA = 4.8 cm. (ii) Draw the locus of a point which moves so that it is always 2.5 cm from B. (iii) Draw the locus of a point which moves so that it is equidistant from the sides BC and CA. (iv) Mark the point of intersection of the loci with the letter P and measure PC.

Steps of Construction: (i) Construct \[BC\text{ }=\text{ }3.2\text{ }cm\] long. (ii) Taking B as centre and 5.5 cm radius and C as centre and 4.8 cm radius construct arcs intersecting each other at...

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Points A, B and C represent position of three towers such that AB = 60 mm, BC = 73 mm and CA = 52 mm. Taking a scale of 10 m to 1 cm, make an accurate drawing of Δ ABC. Find by drawing, the location of a point which is equidistant from A, B and C and its actual distance from any of the towers.

According to ques, \[AB\text{ }=\text{ }60\text{ }mm\text{ }=\text{ }6\text{ }cm\] \[BC\text{ }=\text{ }73\text{ }mm\text{ }=\text{ }7.3\text{ }cm\] \[CA\text{ }=\text{ }52\text{ }mm\text{ }=\text{...

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In the diagram, A, B and C are fixed collinear points; D is a fixed point outside the line. Locate:(iii) the points R on AB such that DR = 4 cm. How many such points are possible? (iv) the points S such that CS = DS and S is 4 cm away from the line CD. How many such points are possible?

Here the points A, B and C are collinear and D is any point which is outside AB.   (iii) Taking D as centre and 4 cm radius construct an arc which intersects AB at R and R’ now R and R’ are the...

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Construct a triangle ABC with AB = 5.5 cm, AC = 6 cm and ∠BAC = 1050. Hence: (i) Construct the locus of points equidistant from BA and BC. (ii) Construct the locus of points equidistant from B and C. (iii) Mark the point which satisfies the above two loci as P. Measure and write the length of PC.

Following are the Steps of Construction: Construct a triangle ABC with AB = 5.5 cm, AC = 6 cm and ∠BAC = 1050. (i) The points which are equidistant from BA and BC lies on the bisector of ∠ABC. (ii)...

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Use ruler and compasses only for this question.(i) Construct the locus of points inside the triangle which are equidistant from B and C. (ii) Mark the point P which is equidistant from AB, BC and also equidistant from B and C. Measure and record the length of PB.

Since, In Δ ABC, AB = 3.5 cm, BC = 6 cm and ∠ABC = 600 (i) Construct a perpendicular bisector of BC which intersects BY at point P. (ii) It is given that point P is equidistant from AB, BC and also...

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A straight line AB is 8 cm long. Locate by construction the locus of a point which is: (i) Equidistant from A and B. (ii) Always 4 cm from the line AB. (iii) Mark two points X and Y, which are 4 cm from AB and equidistant from A and B. Name the figure AXBY.

Following are the Steps of Construction, (i) Construct a line segment AB = 8 cm. (ii) Using compasses and ruler, construct a perpendicular bisector l of AB which intersects AB at the point O. (iii)...

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Describe completely the locus of points in each of the following cases: (v) centre of a circle of varying radius and touching two arms of ∠ADC. (vi) centre of a circle of varying radius and touching a fixed circle, centre O, at a fixed point A on it.

(v) Construct the bisector BX of ∠ABC. hence, this bisector of an angle is the locus of the centre of a circle having different radii. now, any point on BX is equidistant from BA and BC which are...

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