lmagine an equilateral triangle and a square. The triangle has sides of 10 m and the square has sides of 15 m. One ant walks completely round the triangle twice and a beetle which walks two and a half times as fast starts walking at the same time around the square. How many laps of the square would the beetle have made in the same time ? .....

Question

lmagine an equilateral triangle and a square. The triangle has sides of 10 m  and the square has sides of 15 m. One ant walks completely round the triangle twice and a beetle which walks two and a half times as fast starts walking at the same time around the square. How many laps of the square would the beetle have made in the same time ? .....

Steve · Answer

perimters:
triangle = 30
square: 60

ant walks 60 m
in same time, beetle walks 2.5*60 = 150 m
150/60 = 2.5 laps

or, just notice that the distance walked by the ant is one lap of the square, so the beetle, walking 2.5 times as fast, walks 2.5 laps on the square.