Two-digit multiplication and remainders
Answers are for parents and teachers.
1
Find 56 × 40 and 56 × 43.
56 × 40 = 2,240. 56 × 3 = 168. 56 × 43 = 2,240 + 168 = 2,408.
2
Draw four boxes for 34 × 25 and find the product.
30 × 20 = 600; 30 × 5 = 150; 4 × 20 = 80; 4 × 5 = 20. 600 + 150 + 80 + 20 = 850.
3
A school has 24 classes with 36 pupils in each. How many pupils are there? Estimate first.
Estimate 25 × 40 = 1,000. Exact: 36 × 4 = 144 and 36 × 20 = 720. 144 + 720 = 864 pupils.
4
Find 305 × 12 with the standard algorithm.
305 × 2 = 610 and 305 × 10 = 3,050. 610 + 3,050 = 3,660.
5
A ribbon 100 cm long is cut into pieces of 12 cm. How many full pieces can be cut and how much ribbon is left over?
100 ÷ 12 = 8 R 4. 8 pieces and 4 cm left.