Ai Tong School P5 SA1 2006 Math (Q47)

Some villagers were building a bridge across a river. On the first week, they built 210 m of the bridge. On the second week, they built 1/5 of the remaining length. How long was the bridge if the total length that they had built on the first two weeks was twice the remaining length to be built?

Solution



7 units ----- 210
1 unit ----- 210 divided by 7 = 30

Length of bridge ----- 210m + 5 units
= 210m + (5 x 30m)
= 210m + 150m
= 360m

Answer: The length of the bridge is 360m.