Multiplying with powers of ten, area models and partial products
Answers are for parents and teachers.
1
Work out 63 × 10,000 and 4,500 × 200.
630,000 and 900,000 (45 × 2 = 90, then four zeros).
2
Use an area model for 38 × 24.
30 × 20 = 600, 8 × 20 = 160, 30 × 4 = 120, 8 × 4 = 32. Sum: 912.
3
Find 507 × 34 with partial products.
507 × 4 = 2,028 and 507 × 30 = 15,210. Sum: 17,238.
4
Seif’s shop sells 125 notebooks every day. How many notebooks does it sell in 24 days?
125 × 20 = 2,500 and 125 × 4 = 500. Sum: 3,000 notebooks.
5
Use 100 − 1 to work out 45 × 99.
45 × 100 − 45 = 4,500 − 45 = 4,455.