Question

Alka thinks of a number ,she added to 5 it. To this she added of the double of the original number and then subtract 10 from it to get 40.Find the number.

Answer 1

Let's take the number she thought as 'x'.

So, x+5+2x-10=40, as given.

Let's now solve this equation:

x + 5 + 2x - 10 = 40.
3x-5 = 40.
3x = 40+5.
x = 45/3.
x = 15.

Therefore, the number she initially started with is 15.

Answer 2

Answer:

Let's the no. she thought as x

She adds of the original is 2x

Let's solve,

x+5+2x-10=40

=> 3x-5=40

=> 3x =40+5

=> x = 45/3

=> x = 15

Hence,

The no. she thought as x = 15

She adds of the original is 2x = 2 × 15 = 30