20 minutes, then stopCostume 1Wed 7 October1 / 4
Choose one of these two
1 Basketball 2 Shopping — do sheet 1 or sheet 2, then everyone does 3 and 4
Name Date
1 · Basketball — shooting, roughlySuccess rate is really said in percent. Here we ask one in how many goes in: shots taken ÷ shots made. When the numbers are awkward, estimate first.
Example 60 shots, 20 made → 60 ÷ 20 = 3 → one in 3
1A player took 84 shots and made 28. One in how many goes in?
28 → 30. Estimate first, then divide.
2Player A made 22 of 88 shots, player B made 30 of 90. For each, one in how many goes in? Who shoots better?
3A player took 58 shots and made 19. Say "about one in ...?" from an estimate first, then work out 58 ÷ 19 by long division.
What does the remainder stand for?
2 · Shopping — the total before the tillWork out a rough total before you reach the till. Round, then add (an estimate). How many you can buy at one price is a division.
Example 188 yen and 304 yen → 200 + 300 → about 500 yen
1You buy three things at 298 yen, 412 yen and 199 yen. Round each to the nearest hundred and estimate the total.
2Gum costs 47 yen each. You buy as many as you can with 300 yen. How many, and how much change?
47 → 50. Try 300 ÷ 50 = 6.
3You buy things at 698 yen, 405 yen and 296 yen, and have 1,600 yen. Round each up to the hundred. Is it enough?
Rounding up gives an estimate bigger than the real total.
3 · From here, everyone
4Work out 275 ÷ 34 with long division.
34 → 30. Try 270 ÷ 30 = 9 and multiply back.
5Estimate 4,829 + 3,174 by rounding each to the nearest hundred. Say "about ..." out loud before you write.
687 people ride in boats that hold 12 each. How many boats are needed?
7You pay 3,210 yen using only 1,000-yen notes. How many notes are needed?
8Work out 412 ÷ 57 with long division.
57 → 60. 60 × 7 = 420 is close to 412.
9Work out 252 ÷ 36 with long division.
After subtracting, is the remainder smaller than 36?