Question

Raj wanted to type the first 999 natural numbers, how many times does he have to press the keys

Answer 1

Answer:

2889 times

Step-by-step explanation:

Since the numbers from 1 to 9 consist of single digit so

To type from 1 to 9 Raj have to press keys = 9 times

Since the numbers from 10 to 99 consist of two digits so

To type from 10 to 99 Raj have to press keys = 90 * 2 = 180 times

Since the numbers from 100 to 999 consist of 3 digits so

From 100 to 999 Raj have to press keys = 900 * 3 = 2700 times

Total number of keys = 9 + 180 +2700 = 2889 times

Thus

Raj have to press keys for 2889 times