Question Detail

In a mixture 60 litres, the ratio of milk and water 2 : 1. If the this ratio is to be 1 : 2, then the quanity of water to be further added is

20 liters
30 liters
50 liters
60 liters

Answer: Option D

Explanation:

Quantity of Milk = 60*(2/3) = 40 liters
Quantity of water = 60-40 = 20 liters

As per question we need to add water to get quantity 2:1

=> 40/(20+x) = 1/2
=> 20 + x = 80
=> x = 60 liters

1. If a:b = 2:3 and b:c = 4:3, then find a:b:c

8:12:9
2:3:8
2:3:9
2:3:12

Answer: Option A

Explanation:

\begin{aligned}
a:b = 2:3 \\
b:c = 4:3 = (4*\frac{3}{4} : 3*\frac{3}{4}) \\
= 3:\frac{9}{4} \\
a:b:c = 2:3:\frac{9}{4} \\
= 8:12:9
\end{aligned}

2. Two numbers are respectively 20% and 50% more than a third number. The ratio of the two numbers is

Answer: Option C

Explanation:

Let the third number be x.
First Number (120/100)*x = 6x/5
Second Number (150/100)*x = 3x/2

Ratio = 6x/5:3x/2
=> 4:5

3. The salaries of A, B and C are of ratio 2:3:5. If the increments of 15%, 10% and 20% are done to their respective salaries, then find the new ratio of their salaries.

20:33:60
21:33:60
22:33:60
23:33:60

Answer: Option D

Explanation:

Let A salary be 2k
B salary be 3k and C salary be 5k

\begin{aligned}
\text{A's new salary = }\frac{115}{100}*2k \\
= \frac{23}{10}k \\
\text{B's new salary = }\frac{110}{100}*3k \\
= \frac{33}{10}k \\
\text{C's new salary = }\frac{120}{100}*5k \\
= 6k \\

\text{New ratio = }\\
\frac{23k}{10}:\frac{33k}{10}:6k \\
= 23:33:60 \\
\end{aligned}

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

Answer: Option D

Explanation:

\begin{aligned}
a:b = 2:3 \\
b:c = 5:8 = (5*\frac{3}{5} : 8*\frac{3}{5}) \\
= 3:\frac{24}{5} \\
a:b:c = 2:3:\frac{24}{5} \\
= 10:15:24 \\
b = 98*\frac{15}{49} \\
= 30
\end{aligned}

5. If 40% of a number is equal to two-third of another number, what is the ratio of first number to the second number.

Answer: Option D

Explanation:

Let the first number is A and second number is B.

As per question

\begin{aligned}
\frac{40}{100}A = \frac{2}{3}B \\

\frac{A}{B} = \frac{2}{3}*\frac{100}{40} \\
\frac{A}{B} = \frac{5}{3} \\
=> A:B = 5:3

\end{aligned}