Upper and lower bounds Quiz

1. A number $x=3.4$ is rounded to 1 decimal place. What is its upper bound?

• A. $3.5$
• B. $3.45$
• C. $3.41$
• D. $3.35$

2. $a=8$ and $b=5$, each to the nearest integer. Find the upper bound of $a-b$.

• A. $3$
• B. $3.5$
• C. $4$
• D. $2$

3. A rectangle is $12$ cm by $5$ cm, each to the nearest cm. Find the lower bound of its area.

• A. $51.75$ cm$^2$
• B. $60$ cm$^2$
• C. $68.25$ cm$^2$
• D. $52.5$ cm$^2$

4. A distance of $60$ m (nearest $10$ m) is covered in $5$ s (nearest second). Find the upper bound of the speed.

• A. $12$ m/s
• B. $10$ m/s
• C. $13.3$ m/s
• D. $14.4$ m/s

5. The bounds of a result are $8.46$ and $8.54$. To what accuracy can the result be stated?

• A. $8.46$
• B. $8.54$
• C. $8.5$
• D. $9$