Finally, for 4 + 4, multiply 4 by 5 (4 x 5 = 20), and then add 20 four times (20 + 20 + 20 + 20 = 80).
For 3 + 3, multiply 3 by 5 (3 x 5 = 15), and then add 15 three times (15 + 15 + 15 = 45).
For 2 + 2, you multiply 2 by 5 (2 x 5 = 10), and then you add 10 to itself (10 + 10 = 20).
1 + 1 = 5 2 + 2 = 20 3 + 3 = 45 4 + 4 = ?.
Multiply it by 5 (1 x 5 = 5), and that’s the answer.
