Question

the result of a number, when decreased by 135% is 60. Find the number.​

Answer 1

Answer:

Since the original quantity, x, has been reduced by 15% to give 60, then we observe that this 60 must be equal to 85 per-cent of the original value (or just 85%). Like-wise, the original value, x, must be equal to 100%. Thus, we may write:

x = 100%…………………………………………………………………………………………….(1)

and:

60 = 85%…………………………………………………………………………………………….(2)

Dividing Eq. (1) by Eq. (2), we have:

x/60 = 100/85………………………………………………………………………………………(3)

Multiplying both sides of Eq. (3) by 60, we obtain:

x = 60 * 100/85 = 6000/85 = 70.59

Now, let’s check what we get by subtracting 15% from 70.6.

15% of 70.59 = (15/100) * 70.59 = 10.59

And 70.59 - 10.59 = 60

which is correct.

[Note, we could also have calculated 85% of 70 to immediately give:

(85/100) * 70.59 = 60]

Hence, the original value is x = 70.59 to two decimal places.