1/4 of a rod was painted red. 2/5 was painted orange and 2/7 of the remainder was painted yellow. The yellow section was 20cm lo
1 answer:
Answer: 200cm long
Step-by-step explanation:
Let the length of the rod be x
red = 1/4 of the rod , which means 1/4 of x
orange = 2/5 of x
The remainder = x - ( +
)
= x - ()
=
yellow = 2/7 of the remainder , that is
yellow = 2/7 of
yellow =
and it was given that the yellow section was 20cm long , that is
= 20cm
x = 20 x10
x = 200
Therefore the rod was 200cm long
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