(a) Estimate the sum of 573 and 264. 573 rounds to
1
to the nearest 100.
to the nearest 100.
264 rounds to
+ = (b) Copy and complete the calculation using the two different methods.
H T O 5 7 3 + 2 6 4
573 + 264 = +
=
+
=
+
=
+
Which method did you prefer for this calculation? Why?
1 Which methods will you use to solve these? Make estimates first. Will each answer be odd or even?
(a) 543 + 394 (b) 394 + 553 (c) 594 + 343 (d) 343 + 494 (e) 252 + 253 (f ) 352 + 353 (g) 262 + 263 (h) 462 + 463 What do you notice about the answers for each set of four calculations? Can you explain why?
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04/05/2022 15:50
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