Match expression to the story: 1. 5r, 2. x+10, 3. 30-x

1. Expression: $5x$ Story a: "You buy 5 pens that cost $x$ shillings each." If each pen costs $x$ shillings and you buy 5 pens, the total cost is $5 \times x$, which is $5x$. This is a match.

2. Expression: $x + 10$ Story b: "Your age now plus 10 years." If your current age is $x$, then your age plus 10 years is $x + 10$. This is a match.

3. Expression: $20 - x$ Story c: "20 shillings spent, $x$ shillings left." This story can be interpreted as: You started with 20 shillings, and you spent $x$ shillings. The amount of money you have left is $20 - x$. This is a match.

• $1. \ 5x \quad \rightarrow \quad \text{a. You buy 5 pens that cost } x \text{ shillings each.}$
• $2. \ x + 10 \quad \rightarrow \quad \text{b. Your age now plus 10 years.}$
• $3. \ 20 - x \quad \rightarrow \quad \text{c. 20 shillings spent, } x \text{ shillings left.}$

Here are the matches:

1. $\boxed{5x \text{ matches a}}$
2. $\boxed{x + 10 \text{ matches b}}$
3. $\boxed{20 - x \text{ matches c}}$