Question

A number is totally even if all its digits are even. For instance, the numbers 2022 is totally even. How many four-digit totally even numbers X are there such that X + 2022 is totally even?

Answer 1

Answer:

The units digit of our number should be and can be any of 0, 2, 4, 6  (four opportunities).

The tens  digit of our number should be and can be any of 0, 2, 4, 6  (four opportunities).

The hundreds digit of our number should be and can be any of 0, 2, 4, 6, 8  (five opportunities).

The thousands digit of our number should be and can be any of 2, 4, 6  (three opportunities).

So, there are 4*4*5*3 = 16*15 = 240  such 4-digits totally even numbers, satisfying the condition.     ANSWER

Step-by-step explanation: