plss tell the answer

Question

sally cuts a piece of ribbon 147 cm long into three pieces in the ratio 5:3:2, what is length of the longest ribbon

Answer 1

147/2 = 73.5 cm

5:3:2 means the pieces are 1/2, 3/10 and 1/5 of 147

5/(5+3+2) = 5/10 = 1/2 of 147 = 73.5 = 73 1/2 cm

3/(5+3+2) = 3/10 of 147 = 44.1 cm

2/(5+3+2) = 2/10 = 1/5 of 147 = 29.4

73.5 + 44.1 + 29.4 = 147 cm