Maths~!help~~~

Ricky has 42 rods of type A and 48 rods of type B. The length of eachtype A rod is 80 cm and each type B rod is 1 m 20 cm.
He cut all the rods into equal pieces with the largest possible length.
(a) How many small rods did he get in total?
(b) what percentage of the small rods in (a) are cut from type A?


(a)
Length of each type A rod = 80 cm
Length of each type B rod = 1 m 20 cm = 120 cm

The H.C.F. of 80 and 120 = 40
Hence, length of each small rod = 40 cm

Number of small rods he get in total
= 42*(80/40) + 48*(120/40)
= 84 + 144
= 228

(b)
Percentage of small rods cut from type A
= (84/228) * 100%
= (36 and 16/19)%