first, you need a common denominator, which would be 40, then you'll take the 5 in 5/8 and multiply it by 5 because that's what you did to the denominator, which is 25. then multiply the 2 in 2/5 by 8 because that's what you multiplied the denominator by. so then you have 25/40+16/40 which equals 41/40, then you'd divide 41÷40 to get 1 1/40, which is your answer