Question

pls ans with explanation . beg uuu​

Answer 1

Answer:

1st 180 natural numbers means 1,2,3,4,.....180.

from 1,2,3...9,

Total no of times he had to press the numbered keys are 9,

from 10,11,12,....99,

total no of keys =90*2=180,

from 100,101,102,....180.

total no of keys=81*3=243,

therefore,

total no of numbered keys he had to press =9+180+243=432.

Hope it helps u...