Solving Problems with Rounding

In this lesson, you will learn how to solve problems working with lower and upper bounds to find maximum and minimum values.

Quiz:

Intro quiz - Recap from previous lesson

Before we start this lesson, let’s see what you can remember from this topic. Here’s a quick quiz!

Question 1

Question 2

Question 3

Question 4

Question 5

Question 6

Q1.Write down an inequality expressing the lower and upper bound for 23.071kg to three decimal places

23.0705 ≤ k < 23.0715 23.0705 ≤ k ≤ 23.0715 23.0710 ≤ k < 23.0715 23.0705 ≤ k < 23.0714

1/6

Q2.Write down an inequality expressing the lower and upper bound for 0.3m given to 1 significant figure

0.25 < m ≤ 0.35 0.25 ≤ m < 0.349999 0.25 ≤ m < 0.35 0.25 ≤ m ≤ 0.35

2/6

Q3.Write down an inequality expressing the lower and upper bound for 0.023 given to 2 significant figure

LB = 0.0225 , UB = 0.0235 0.0225 ≤ x < 0.0235 0.0225 ≤ x ≤ 0.02349 0.0224 ≤ x < 0.0235

3/6

Q4.The length of a football field is 500m to the nearest 10m. Jacob says the lower bound is 450m and the upper bound is 550m. Is he correct? Give a reason for your answer.

Yes, he is correct No, he is not correct

4/6

Q5.The mass of a loaf of bread is given as 1.7kg to the nearest 0.1kg. Write an inequality expressing the upper and lower bound of the mass.

1.65kg ≤ m < 1.75kg 1.649kg ≤ m < 1.749kg 1.65kg ≤ m ≤ 1.75kg 1.645kg ≤ m ≤ 1.745kg

5/6

Q6.A piece of string is measured at 1.57m to two decimal places. Write an inequality expressing the lower and upper bound within which l, the actual length of string lies.

1.564999 ≤ l ≤1.574999 1.565 ≤ l ≤1.575 1.565 ≤ l < 1.575 1.565 ≤ l < 1.570

6/6

Quiz:

Intro quiz - Recap from previous lesson

Before we start this lesson, let’s see what you can remember from this topic. Here’s a quick quiz!

Question 1

Question 2

Question 3

Question 4

Question 5

Question 6

Q1.Write down an inequality expressing the lower and upper bound for 23.071kg to three decimal places

23.0705 ≤ k < 23.0715 23.0705 ≤ k ≤ 23.0715 23.0710 ≤ k < 23.0715 23.0705 ≤ k < 23.0714

1/6

Q2.Write down an inequality expressing the lower and upper bound for 0.3m given to 1 significant figure

0.25 < m ≤ 0.35 0.25 ≤ m < 0.349999 0.25 ≤ m < 0.35 0.25 ≤ m ≤ 0.35

2/6

Q3.Write down an inequality expressing the lower and upper bound for 0.023 given to 2 significant figure

LB = 0.0225 , UB = 0.0235 0.0225 ≤ x < 0.0235 0.0225 ≤ x ≤ 0.02349 0.0224 ≤ x < 0.0235

3/6

Q4.The length of a football field is 500m to the nearest 10m. Jacob says the lower bound is 450m and the upper bound is 550m. Is he correct? Give a reason for your answer.

Yes, he is correct No, he is not correct

4/6

Q5.The mass of a loaf of bread is given as 1.7kg to the nearest 0.1kg. Write an inequality expressing the upper and lower bound of the mass.

1.65kg ≤ m < 1.75kg 1.649kg ≤ m < 1.749kg 1.65kg ≤ m ≤ 1.75kg 1.645kg ≤ m ≤ 1.745kg

5/6

Q6.A piece of string is measured at 1.57m to two decimal places. Write an inequality expressing the lower and upper bound within which l, the actual length of string lies.

1.564999 ≤ l ≤1.574999 1.565 ≤ l ≤1.575 1.565 ≤ l < 1.575 1.565 ≤ l < 1.570

6/6

Video

Play video

Click on the play button to start the video. If your teacher asks you to pause the video and look at the worksheet you should:

Click "Close Video"
Click "Next" to view the activity

Your video will re-appear on the next page, and will stay paused in the right place.

Worksheet

PDF

PPTX

Google

These slides will take you through some tasks for the lesson. If you need to re-play the video, click the ‘Resume Video’ icon. If you are asked to add answers to the slides, first download or print out the worksheet. Once you have finished all the tasks, click ‘Next’ below.

Quiz:

Solving Problems with rounding

Don’t worry if you get a question wrong! Forgetting is an important step in learning. We will recap next lesson.

Question 1

Question 2

Question 3

Question 4

Question 5

Question 6

Q1.A classroom is measured 5.4 x 3.4 metres, measured to 1 d.p. Calculate the lower bound of the area of the room.

17.889 𝑐𝑚^2 17.9225 𝑐𝑚^2 18.36 𝑐𝑚^2 18.8025 𝑐𝑚^2

1/6

Q2.James ran a distance of 400m in a time of 25.2 seconds. The distance of 400m was measured to the nearest 10 metres. The time of 25.2 was measured to the nearest tenth of a second. Work out the upper bound James' average speed.

16.10 m/s 16.04 m/s 15.7 m/s 16.07 m/s

2/6

Q3.James ran a distance of 400m in a time of 25.2 seconds. The distance of 400m was measured to the nearest 10 metres. The time of 25.2 was measured to the nearest tenth of a second. Work out the lower bound James' average speed.

15.71 m/s 15.69 m/s 15.64 m/s 15.67 m/s

3/6

Q4.Carl measured the length and width of a rectangle. He measured the length to be 19cm correct to the nearest centimetre. He measured the width to be 20cm correct to the nearest 10cm. Calculate the lower bound for the area of this rectangle.

380 cm^2 277.5 cm^2 292.5 cm^2 370 cm^2

4/6

Q5.6 heights are listed, given to one decimal place: 4.6cm, 6.3cm, 9.8cm, 3.2cm, 5.7cm, 3.6cm. Work out the greatest possible mean.

5.58cm 5.53cm 5.98cm 5.48cm

5/6

Q6.A circle has an area of 130cm^2 to the nearest 10cm^2. Work out the upper bound of the radius. Give your answer to 3 d.p.

39.789 6.433 6.555 6.308

6/6

Quiz:

Solving Problems with rounding

Don’t worry if you get a question wrong! Forgetting is an important step in learning. We will recap next lesson.

Question 1

Question 2

Question 3

Question 4

Question 5

Question 6

Q1.A classroom is measured 5.4 x 3.4 metres, measured to 1 d.p. Calculate the lower bound of the area of the room.

17.889 𝑐𝑚^2 17.9225 𝑐𝑚^2 18.36 𝑐𝑚^2 18.8025 𝑐𝑚^2

1/6

Q2.James ran a distance of 400m in a time of 25.2 seconds. The distance of 400m was measured to the nearest 10 metres. The time of 25.2 was measured to the nearest tenth of a second. Work out the upper bound James' average speed.

16.10 m/s 16.04 m/s 15.7 m/s 16.07 m/s

2/6

Q3.James ran a distance of 400m in a time of 25.2 seconds. The distance of 400m was measured to the nearest 10 metres. The time of 25.2 was measured to the nearest tenth of a second. Work out the lower bound James' average speed.

15.71 m/s 15.69 m/s 15.64 m/s 15.67 m/s

3/6

Q4.Carl measured the length and width of a rectangle. He measured the length to be 19cm correct to the nearest centimetre. He measured the width to be 20cm correct to the nearest 10cm. Calculate the lower bound for the area of this rectangle.

380 cm^2 277.5 cm^2 292.5 cm^2 370 cm^2

4/6

Q5.6 heights are listed, given to one decimal place: 4.6cm, 6.3cm, 9.8cm, 3.2cm, 5.7cm, 3.6cm. Work out the greatest possible mean.

5.58cm 5.53cm 5.98cm 5.48cm

5/6

Q6.A circle has an area of 130cm^2 to the nearest 10cm^2. Work out the upper bound of the radius. Give your answer to 3 d.p.

39.789 6.433 6.555 6.308

6/6

Lesson summary: Solving Problems with Rounding

It looks like you have not attempted both the quizzes.

To share your results with your teacher please complete both the quizzes.

The next lesson in Accuracy and estimation is "Estimation"

Browse Oak's lessons:

Subjects Schedule