Question

How many prime no are less than 100 and greater than 3 in form 4x+1 5y_1?

Answer 1

$\huge{\boxed{\mathtt{\red{ANSWER}}}}$

for condition 5y+1--19,29,59,79,89,

for condition 4x+1---5,13,17,,29,37,41,53,61,88,97.

For conditions both satisfying = (29,89) = 2 Numbers ..