Write hundred, thousand, ten thousand, one lakh, ten lakhs and one crore as powers of 10.
Hundred = 100 = 10 × 10 = (10)2
Thousand = 1000 = 10 × 10 × 10 = (10)3
Ten thousand = 10000 = 10 × 10 × 10 × 10 = (10)4
One lakh = 100000 = 10 × 10 × 10 × 10 × 10 = (10)5
Ten lakhs = 1000000 = 10 × 10 × 10 × 10 × 10 × 10 = (10)6
One crore = 10000000 = 10 × 10 × 10 × 10 × 10 × 10 × 10 = (10)7