Question

Colin has 10 metal rods. Each rod is 90 cm long when rounded to the nearest centimetre (cm). He lays out the rods in a straight line, end to end. What is the smallest possible total length, in cm, of the line of rods?

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Answer 1

895 cm

Step-by-step explanation:

89.4 cm rounds to 89 cm when rounded to the nearest centimeter, but 89.5 cm rounds to 90 cm. The smallest number that rounds to 90 when rounded to the nearest unit is 89.5.

If all rods are 89.5 cm long, then each one rounded to the nearest cm would be 90 cm long.

10 × 89.5 cm = 895 cm

Answer 2

The smallest possible total length of the line of rods is 900 cm.

Step-by-step explanation:

To find the smallest possible total length of the line of rods, we need to add up the lengths of all the rods. Each rod is 90 cm long when rounded to the nearest centimeter. Since Colin has 10 metal rods, the smallest possible total length of the line of rods is 10 x 90 = 900 cm.