The sum of three numbers is 98. If the ratio of the first to second is 2 : 3 and that of the second to the third is 5 : 8, then the second number is:

Correct Answer: Rs. 1600

Explanation:

Let the salaries of Maneela and Shanthi one year before be M1, S1 & now be M2, S2 respectively.

Then, from the given data,

M1/S1 = 3/4  .....(1)

M1/M2 = 4/5 .....(2)

S1/S2 = 2/3  .....(3)

and M2 + S2 = 4160  .....(4)

 

Solving all these eqtns, we get M2 = Rs. 1600.

Correct Answer: 30

Explanation:

$$\begin{gathered} 3 \\ 3 2 + 3 = 12 \\ 5 \\ 5 2 + 5 = 30 \end{gathered}$$

Correct Answer: Rs. 6000

Explanation:

The wages of labourers in a factory increases in the ratio 22:25 and there was a reduction in the number of labourers in the ratio 15:11. Find the original wage bill if the present bill is Rs 5000 ?
Ratio of increase of wages = 22:25
Ratio of decrease of labourers = 15:11
Compound ratio of wages of labourers = 22 x 15 : 25 x 11 = 330:275
Final bill = Rs. 5000
For 275 ratio wages = Rs. 5000
For 1 ratio wages = 5000/275
For 330 ratio wages = 5000/275 x 330 = Rs. 6000

Correct Answer: 12

Explanation:

Given ratio = 7 : 5 : 3 : 4, Sum of ratio terms = 19.

Smallest part =  (76*3/19)  = 12

Correct Answer: (x -y) / ( x + y)

Explanation:

Let the third proportional to  x 2 - y 2 and  x - y be z. Then, 

 

x 2 - y 2 : x - y : : x - y : z  

 

= > x 2 - y 2 * z = x - y 2  

 

=> z= x - y 2 x 2 - y 2 = x - y x + y

Correct Answer: 3:4

Explanation:

m + n m - n = 7 x x ? m n = 4 x 3 x  

 

Again    m n = 12 x 2 

 

and         mn =60x  

 

so,  60 x = 12 x 2 ? x = 5    

 

=>  m= 20  and    n= 15

 

Hence,     1 m : 1 n = 1 20 : 1 15 = 3 : 4

Correct Answer: 48

Explanation:

If you double the sides of a cube, the ratio of the surface areas of the old and new cubes will be 1: 4. The ratio of the volumes of the old and new cubes will be 1: 8.

Weight is proportional to volume. So, If the first weighs 6 pounds, the second weighs 6x8 pounds =48.

Correct Answer: Rs. 175.5

Explanation:

Let the price of required variety = Rs. P/kg

Then, respective amounts were m kg, m kg and 2m kg

= 126m + 135m + 2pm = 153 x 4m

=> 2p = 351

p = 175.5 / kg

Correct Answer: 45 Years

Explanation:

The ratio of the ages of A and B is 3 : 5.
The ratio of the ages of B and C is 3 : 5.

B's age is the common link to both these ratio. Therefore, if we make the numerical value of the ratio of B's age in both the ratios same, then we can compare the ages of all 3 in a single ratio.

The can be done by getting the value of B in both ratios to be the LCM of 3 and 5 i.e., 15.

The first ratio between A and B will therefore be 9 : 15 and
the second ratio between B and C will be 15 : 25.

Now combining the two ratios, we get A : B : C = 9 : 15 : 25.

Let their ages be 9x, 15x and 25x.
Then, the sum of their ages will be 9x + 15x + 25x = 49x

The question states that the sum of their ages is 147.
i.e., 49x = 147 or x = 3.

Therefore, B's age = 15x = 15*3 = 45

Correct Answer: 7556

Explanation:

Let ratio of the incomes of Pavan and Amar be 4x and 3x

and Ratio of their expenditures be 3y and 2y

4x - 3y = 1889 ......... I

and

3x - 2y = 1889 ...........II

I and II

y = 1889

and x = 1889

Pavan's income = 7556