Measurement (mass & weight): Harp Seal
The Problem
For12 days after her birth, Harriet was fattened up on her mother’s milk. During this time, she put on 2 kg of weight every day. Once the 12 days were over, Harriet weighed 34 kg.
Harriet is now a fully-grown adult. She weighs 120 kg.
1) What was Harriet the harp seal’s birth weight?
2) Can you work out how many times heavier Harriet’s fully-grown adult weight is than her weight at birth?
Compare your solution with a friend’s. What is the same? What is different?
Did you know?
Elephant seals are the largest of all the seal species. Adult males can weigh as much as 2,300 kg and be as much as 5 m in length.
Visualising the Problem and Getting Started
Miri said, “It is impossible to solve the two problems because we are not told what Harriet’s birth weight is.” Do you agree with Miri? Discuss with a partner.
