Answer:
a + b = 1 or 4
Step-by-step explanation:
The integer = 3a5b
The factors of the integer includes 5 and 6
∴ 5 × 6 = 30 is a factor of the integer hence 10 is also a factor which gives b = 0
We check for factors of four digit numbers with the first digit = 3, last digit = 0, penultimate to the last digit = 5 and divisible by 30
We have a50 divisible by 30, which gives, a5 divisible by 3 which includes
15 and 45 hence a can be 1 or 4 and a + b = 1 + 0 = 1 or 4 + 0 = 4.
