how many positive even integers less than 100 contain digits 3 or 7 ?
"two digit numbers : 3 at tens place : 30 , 32,34 , 36,38 7 at tens place : 70 , 72,74 , 76,78 if 3 and 7 is at units place , the number cant be even total : 5 + 5 = 10 answer d"
multiply(3, const_2)