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Recall
Bounds in calculations — objective 1
Maths4U Original · Short practice
A rectangle has recorded length 15 cm and width 7 cm. Each was independently rounded to the nearest \(\displaystyle \frac{1}{10}\) cm. Both true dimensions are positive.
Find a lower bound for the rectangle area in \(\displaystyle \mathrm{cm}^{2}\).
Enter one exact number or fraction unless the question specifies rounding. If it asks for a coefficient of π, enter that coefficient only. Give full reasoning separately for written problems.
Fresh review variant
Bounds in calculations — objective 1
Maths4U Original · Short practice
A rectangle has recorded length 16 cm and width 8 cm. Each was independently rounded to the nearest \(1\) cm. Both true dimensions are positive.
Find a lower bound for the rectangle area in \(\displaystyle \mathrm{cm}^{2}\).
Enter one exact number or fraction unless the question specifies rounding. If it asks for a coefficient of π, enter that coefficient only. Give full reasoning separately for written problems.
Method
Bounds in calculations — objective 2
Maths4U Original · Short practice
A rectangle has recorded length 16 cm and width 8 cm. Each was independently rounded to the nearest \(1\) cm. Both true dimensions are positive.
Find an upper bound for its area in \(\displaystyle \mathrm{cm}^{2}\).
Enter one exact number or fraction unless the question specifies rounding. If it asks for a coefficient of π, enter that coefficient only. Give full reasoning separately for written problems.
Fresh review variant
Bounds in calculations — objective 2
Maths4U Original · Short practice
A rectangle has recorded length 17 cm and width 9 cm. Each was independently rounded to the nearest \(\displaystyle \frac{1}{10}\) cm. Both true dimensions are positive.
Find an upper bound for its area in \(\displaystyle \mathrm{cm}^{2}\).
Enter one exact number or fraction unless the question specifies rounding. If it asks for a coefficient of π, enter that coefficient only. Give full reasoning separately for written problems.
Apply
Bounds in calculations — objective 3
Maths4U Original · Short practice
A rectangle has recorded length 17 cm and width 9 cm. Each was independently rounded to the nearest \(\displaystyle \frac{1}{10}\) cm. Both true dimensions are positive.
Find a lower bound for its perimeter in cm.
Enter one exact number or fraction unless the question specifies rounding. If it asks for a coefficient of π, enter that coefficient only. Give full reasoning separately for written problems.
Fresh review variant
Bounds in calculations — objective 3
Maths4U Original · Short practice
A rectangle has recorded length 18 cm and width 5 cm. Each was independently rounded to the nearest \(1\) cm. Both true dimensions are positive.
Find a lower bound for its perimeter in cm.
Enter one exact number or fraction unless the question specifies rounding. If it asks for a coefficient of π, enter that coefficient only. Give full reasoning separately for written problems.
Check understanding
Bounds in calculations — objective 4
Maths4U Original · Short practice
A rectangle has recorded length 18 cm and width 5 cm. Each was independently rounded to the nearest \(1\) cm. Both true dimensions are positive.
Find an upper bound for its length-to-width ratio.
Enter one exact number or fraction unless the question specifies rounding. If it asks for a coefficient of π, enter that coefficient only. Give full reasoning separately for written problems.
Fresh review variant
Bounds in calculations — objective 4
Maths4U Original · Short practice
A rectangle has recorded length 19 cm and width 6 cm. Each was independently rounded to the nearest \(\displaystyle \frac{1}{10}\) cm. Both true dimensions are positive.
Find an upper bound for its length-to-width ratio.
Enter one exact number or fraction unless the question specifies rounding. If it asks for a coefficient of π, enter that coefficient only. Give full reasoning separately for written problems.