Three numbers, of which the third is equal to 36, form a geometric progression. if 36 is replaced with 20, then the three numbers form an arithmetic progression. find these three numbers.

The answer is either 4, 12, 36 or  100, 60, 36.

Step-by-step explanation: Let the first two numbers be 'a' and 'b'.

According to the question, a, b and 36 forms a geometric series. So, we have

Also, if 36 is replaced by 20, then a, b, 20 will form an arithmetic series. So,

Therefore,

Thus, the three numbers are either 4, 12, 36 or  100, 60, 36.