A number is doubled and 9 is added. If resultant is trebled, it becomes 75. What is that number

Answer: Option C

Explanation:

Let the three integers be x, x+2 and x+4.
Then, 3x = 2(x+4)+3,
x= 11
Therefore, third integer x+4 = 15

Answer: Option D

Explanation:

If the number is x,

Then, x + 17 = 60/x

x2 + 17x - 60 = 0

(x + 20)(x - 3) = 0

x = 3, -20, so x = 3 (as 3 is positive)

Answer: Option C

Explanation:

$$\begin{aligned} => \frac{(x+y)}{(x-y)} = \frac{40}{4} \end{aligned}$$

$$\begin{aligned} => (x+y)= 10(x-y) \end{aligned}$$

$$\begin{aligned} => 9x = 11y => \frac{x}{y} = \frac{11}{9} \end{aligned}$$

Answer: Option C

Explanation:

Let the second number is x, then first is 2x, and third is 1/3(2x)
$$\begin{aligned} =>2x + x + \frac{2x}{3} = 264 <=> \frac{11x}{3} = 264 \end{aligned}$$

$$\begin{aligned} => x = 72 \end{aligned}$$

Answer: Option A