Mathematics for IGCSE & O level - Algebraic Manipulation (Section 7 - No. 42)
What expression does the following describe: If apples cost $2 each and you bought 'a' apples?
2 + a
2a
a/2
2 - a
解释
The total cost is the price per apple multiplied by the number of apples: 2 * a = 2a