Question

If the difference between 75% of a number and 4/5 th of the number is 40. what is the number?​

Answer 1

Answer:

Let the number be

xx

The question says,

either

0.75 x - \frac{4}{5} x = 400.75x−

5

4

x=40

or

\frac{4}{5} x - 0.75 x = 40

5

4

x−0.75x=40

As

\frac{4}{5} x = 0.8x

5

4

x=0.8x

Either

0.05x = 400.05x=40

or

-0.05x = 40−0.05x=40

x

becomes

800800 or -800−800

Answer 2

Answer:

If the difference between 75% of a number and 4/5 if of that number is 40 then what is the number?

Let’s say that the unknown number is “x”. 4/5=80% or 0.8x. 75% is 0.75x.

The question goes thus:

0.8 x-0.75 x=40 or

x(0.8–0.75)=40;

x=40/0.05;

Multiplying numerator and denominator by 100 to get a non decimal denominator, we get x=4000/5 or x=800

You can also do fractions if you don’t care for decimal points.

4/5x-3/4x=40 (since 7%% is 3/4)

x(4/5–3/4)=40;

x (1/20)=40;

x=40*20=800