4 shelves hold 7 boxes each, with 5 pens per box. How many pens?
- 160
- 120
- 140
- 35
Show answer and solution
Correct answer: C. 140
1. Group the factors as (4 × 5) × 7.
2. 4 × 5 = 20, then 20 × 7 = 140.
3. Order of factors does not change the product.
_Source: Wikipedia, Multiplication table (CC BY-SA 4.0, rev 1379867676), Modern times_