Question

7. What percentage of the numbers from 1 to 50 have squares that end in the digit 1? (a) 10 (b) 5 (c) 11 (d) 20​

Answer 1

Answer:

The squares of numbers having 1 and 9 as the unit's digit end in the digit 1.

Such numbers are,

1,9,11,19,21,29,31,39,41,49 i.e.,

There are 10 such numbers.

∴Required percentage

=(10/50×100)%

=20%

therefore d option is correct i.e 20