= Search

Q:

If 1.5x = 0.04y, then the value of ( (y - x) / (y+x) ) is :

A) 73/77	B) 7.3/77
C) 730/77	D) 7300/77

Answer & Explanation Answer: A) 73/77

Explanation:

x / y = 0.04 / 1.5 = 4 / 150 = 2 / 75.

= > ( (y - x) / (y+x) ) = (1 - (x / y)) / ( 1 + ( x / y)) = (1 - 2/75) / (1 + 2/75) = 73/77...

Report Error

View Answer Report Error Discuss

Filed Under: Decimal Fractions

Q:

The third proportional to $(x^{2} - y^{2})$ and $(x - y)$ is :

A) (x + y )	B) (x - y)
C) (x + y) / ( x - y)	D) (x -y) / ( x + y)

Answer & Explanation Answer: D) (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= $\frac{{(x - y)}^{2}}{(x^{2} - y^{2})} = \frac{(x - y)}{(x + y)}$

Report Error

View Answer Report Error Discuss

Filed Under: Ratios and Proportions

Q:

What will be the value of ${(25.732)}^{2} - {(15.732)}^{2}$

A) 214.64	B) 314.64
C) 414.64	D) 412.64

Answer & Explanation Answer: C) 414.64

Explanation:

Can be easily solved with following formula

$(a^{2} - b^{2}) = (a - b) \times (a + b)$

= (25.732 - 15.732 ) x (25.732 + 15.732)

=414.64

Report Error

View Answer Report Error Discuss

Filed Under: Decimal Fractions

Q:

If Rs. 782 be divided into three parts, proportional to $\frac{1}{2} : \frac{2}{3} : \frac{3}{4}$ , then the first part is?

A) Rs. 182	B) Rs. 190
C) Rs. 192	D) Rs. 204

Answer & Explanation Answer: D) Rs. 204

Explanation:

$R s . (782 * \frac{6}{23})$

Given ratio = $\frac{1}{2} : \frac{2}{3} : \frac{3}{4}$ = 6:8:9

1st part = $R s . (782 * \frac{6}{23})$ = Rs. 204

Report Error

View Answer Report Error Discuss

Filed Under: Ratios and Proportions

Q:

A train travelling at a speed of 75 mph enters a tunnel $3 \frac{1}{2}$ miles long. The train is $\frac{1}{4}$ mile long. How long does it take for the train to pass through the tunnel from the moment the front enters to the moment the rear emerges?

A) 2.5 min	B) 3 min
C) 3.2 min	D) 3.5 min

Answer & Explanation Answer: B) 3 min

Explanation:

Total distance covered = $(\frac{7}{2} + \frac{1}{4})$ miles = $\frac{15}{4}$ miles

Time taken = $(\frac{15}{4 * 75})$ hrs = $\frac{1}{20}$ hrs = $(\frac{1}{20} * 60) m i n$ = 3 min

Report Error

View Answer Report Error Discuss

Filed Under: Problems on Trains

Q:

0.1 decates ago, Vijaya was quadrice as old as her daughter Simran. 0.6 decades hence, Vijaya’s age will beat her daughter’s age by 0.9 decades. The proportion of the current ages of Vijaya and Simran is : [ 0.1 Decates =1 Year; quadrice = 4 times]

A) 8:1	B) 10:2
C) 11:4	D) 13:4

Answer & Explanation Answer: D) 13:4

Explanation:

Let, Ages of Vijaya and Simran – 1 year ago was 4A and A years correspondingly.
Then, [(4A + 1) + 6] – [(A + 1) + 6] = 9
3A = 9 => A = 3

Needed Ratio = (4A + 1) : (A + 1) = 13 : 4

Report Error

View Answer Report Error Discuss

Filed Under: Problems on Ages

Q:

The ratio of the ages of Maala and Kala is 4 : 3. The total of their ages is 2.8 decades. The proportion of their ages after 0.8 decades will be [1 Decade = 10 years]

A) 4:3	B) 12:11
C) 7:4	D) 6:5

Answer & Explanation Answer: D) 6:5

Explanation:

Let, Maala’s age = 4A and Kala’s age = 3A
Then 4A + 3A = 28
A = 4
Maala’s age = 16 years
and Kala’s age = 12 years
Proportion of their ages after 8 is = (16 + 8) : (12 + 8)
= 24 : 20
= 6 : 5

Report Error

View Answer Report Error Discuss

Filed Under: Problems on Ages

Q:

A man’s current age is $\frac{2}{5}$ of the age of his father. After 8 years, he will be $\frac{1}{2}$ of the age of his father. What is the age of father at now ?

A) 50	B) 40
C) 33	D) 30

Answer & Explanation Answer: B) 40

Explanation:

Let, father’s current age is A years.
Then, Man’s current age = $[(\frac{2}{5} * A)]$ years.

$[(\frac{2}{5} * A)]$ +8= $(\frac{1}{2}) (A + 8)$

2(2A+40) = 5(A+8)

A = 40

Report Error

View Answer Report Error Discuss

Filed Under: Problems on Ages

Searching for "="

Quick Links