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If 2 : 9 :: x : 18, then find the value of x

  • 2
  • 3
  • 4
  • 6

Answer: Option C

Explanation:

Treat 2:9 as 2/9 and x:18 as x/18, treat :: as =

So we get 2/9 = x/18
=> 9x = 36
=> x = 4

Similar Questions :

1. 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

2. Rs. 120 are divided among A, B, C such that A's share is Rs. 20 more than B's and Rs. 20 less than C's. What is B's share

  • Rs 10
  • Rs 20
  • Rs 24
  • Rs 28

Answer: Option B

Explanation:

Let C = x. Then A = (x—20) and B = (x—40).
x + x - 20 + x - 40 = 120 Or x=60.
A:B:C = 40:20:60 = 2:1 :3.
B's share = Rs. 120*(1/6) = Rs. 20

3. A dog takes 3 leaps for every 5 leaps of a hare. If one leap of the dog is equal to 3 leaps of the hare, the ratio of the speed of the dog to that of the hare is

  • 4:5
  • 9:5
  • 8:5
  • 9:2

Answer: Option B

Explanation:

Dog : Hare = (3*3) leaps of hare : 5 leaps of hare
= 9 : 5

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

  • 10
  • 17
  • 25
  • 30

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 x:y = 1:3, then find the value of
(7x+3y):(2x+y)

  • 14:5
  • 15:5
  • 16:5
  • 17:5

Answer: Option C

Explanation:

let x = 1k and y = 3k, so
\begin{aligned}
= \frac{7(k)+3(3k)}{2(k)+1(3k)} \\
= \frac{16k}{5k} \\
= 16:5
\end{aligned}

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