Zara has forgotten her 4-digit PIN code. She knows the first digit is a factor of 10 and the 4 digits make a number divisible by 2.
How many different sets of 4 digits could it be?

1500

Step-by-step explanation:

we can write the 4-digit PIN as ABCD

A = factor of 10 so,

A = 1, 2 ,5 (3 possible number or we can write n(A) = 3

B and C are number from 0 - 9 so each have 10 possible number n(B) = 10 and n(C) = 10

D makes the whole number cannbe divide by 2. it means that D must even number 2,4,6,8 or 0. so there are 5 possible number n(D) = 5

so to find how many different sets we just multiply all possible number

n(A) x n(B) x n(C) x n(D)

3 x 10 x 10 x 5 = 1500 different sets

the answer for the second equation is (4,0)