Question

find the number of natural number between 101 ana 999 wgich are divisible by both 2 and 5

Answer 1

⇒ Step-by-step explanation:

A = 110 (first number divided by 2 and 5)

Common difference (d) = 10

an = 990  (last no divided by 2 and 5)

an = a + (n - 1) × d

990 = 110 + 10 × n - 10

880 + 10 = 10n

890 = 10n  

n =  $\frac{890}{10}$

n = 89