Specialized Training in Mixed Operations (4A)四年級第一學期“混合運算”專項訓練

林欣欣

I. Calculation.

（1） （105 + 27） × 3 + 56 =

（2） 360 ÷ （6 + 3） –17 =

（3） 220 ÷ 5 – （15 × 2） =

（4） 309 – 12 × （8 + 4） =

（5） （18 – 12） ÷ 2 × 32 =

（6） 77 + （103 × 2） – 159 =

（7） 56 + 135 ÷ 5 × 30 – 75 =

（8） 72 × 30 – 200 ÷ 25 + 8 =

（9） 600 – （12 × 15） ÷ 4 =

（10） 720 ÷ 6 – （140 ÷ 5） =

II. Word problems.

（1）Tommy has 5 boxes of chocolates. Each box contains 24 chocolates. If he eats 12 chocolates from each box， how many chocolates does he have left in total？

（2）A toy store has 50 action figures. If they want to display them in rows with 8 figures in each row， how many rows will there be， and how many figures will be left over？

（3）Sarah is planning a birthday party. She needs 45 balloons for decoration. If each pack of balloons contains 12， how many?packs does she need to buy， and how many balloons will be left over？

（4）There are 72 students in a school bus. If each row of seats holds 8 students， how many rows are there in the bus， and how many students are left without a seat？

（5）A bakery sold 35 cupcakes in the morning and 21 more in the afternoon. How many cupcakes did they sell in total for the day？

（6）They need to repair 726 meters. They have already repaired 285 meters. If they want to finish the remaining work in one week， how many meters do they need to repair each day？

（7）Emily has 36 yuan. She spends 18 yuan on a new toy and 7 yuan on a book. How much money does she have left？

（8）A car left Shanghai at 8：00 in the morning， traveling at a speed of 55 kilometers per hour， and arrived in Nanjing at 6：00 in the evening. Do you know the distance from Shanghai to Nanjing？

（9）A garden has 60 flowers. If 3 out of 4 flowers are roses， how many flowers are roses， and how many are not roses？

（10）If A， when added to 320， equals B; and if B is added to 460， it is three times A. Find the values of A and B.

Keys to Specialized Training in Mixed Operations （4A）

I. （1） 452 （2） 23 （3） 14 （4） 165 （5） 96 （6） 124 （7） 791 （8） 2160 （9） 555

（10） 92

II. （1） 60 （2） 6……2 （3） 4……3 （4） 9; 0 （5） 56 （6） 63 m （7） 11 （8） 550 km

（9） 45; 15 （10） A = 390; B = 710