Column subtraction: Lesson 1: dolphins
The Lesson
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In this exciting lesson, you will need to solve a range of subtraction word problems that feature dolphins. Try using PAWS to arrive at the right answer!
P = Picture the problem in your mind.
A = Annotate the word problem by highlighting the important information.
W = Write down the number sentence that needs to be solved.
S = Solve the number sentence using an efficient strategy.
Useful prior knowledge:
- To confidently subtract a 2-digit number from a 2-digit number (with one exchange).
Did you know?
Scientists think that another reason that a spinner dolphin spins is to shake off parasites that have attached themselves to its skin.
Use PAWS, counters and column subtraction to solve the following word problem.
A twenty-year old spinner dolphin had 176 tiny parasites on its body. After making 56 spinning leaps in the Pacific Ocean, it managed to remove a total of 57 parasites from its body.
How many parasites did the spinner dolphin have on its body after leaping this many times?
