Solve 34 × 8 in two different ways. 34 rounds to
1
, so my estimate is
× 8 =
.
34 × 8 = × 8 = × 8 =
+
=
The answer
is greater/smaller than my estimate of
.
Which method did you prefer for this calculation? Why?
1 Solve these. Remember to make an estimate first. Which methods will you use? Convince your partner.
(a) 50 × 8 (b) 27 × 3 (e) 51 × 8 (f) 37 × 5 What do you notice about your answers to (a) and (e) ? Explain why. 2 (c) 34 × 9 (d) 43 × 6 Use a bar model to represent the problem and then solve it. Winston has six 25c coins. Riana has five 25c coins. How much money do they have in total?
E
How will you represent your thinking? Try Letisha’s idea to solve 28 × 9 and 47 × 9. Why is this a useful strategy?
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04/05/2022 15:50
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