Skip to content
Oak National Academy
Oak National Academy
Teachers
Pupils
New
New
Year 7

Limitations of technology in calculations

I can enter fractions as divisions on a calculator (and other technology) and understand the limitations of the decimal representation that results.

Download all resources
Share activities with pupils
New
New
Year 7

Limitations of technology in calculations

I can enter fractions as divisions on a calculator (and other technology) and understand the limitations of the decimal representation that results.

Download all resources
Share activities with pupils

Lesson details

Key learning points

  1. The line in a fraction means divide.
  2. A calculator can be used to convert a fraction to a decimal using division.
  3. There might be limitations of the decimal representation of fractions.

Common misconception

Incorrect inputting of negative numbers and/or exponents.

Encourage the use of brackets when using exponents.

Keywords

  • Recurring decimals - A recurring decimal is one that has an infinite number of digits after the decimal point

Given the limitations of the calculator, ask pupils to give as many different possible decimals to the number "0.27823728282" which is displayed on a calculator screen. e.g 0.27823728282828282..., 0.27823728281999999, 0.2782372828248392,
Teacher tip

Licence

This content is © Oak National Academy Limited (2024), licensed on Open Government Licence version 3.0 except where otherwise stated. See Oak's terms & conditions (Collection 2).

Video

Skip video

Loading...

Starter quiz

Download starter quiz

6 Questions

Q1.
Using a calculator, calculate the simplified fraction of $$196 \over 190$$.
Correct answer: $$98 \over 95$$
$$96 \over 90$$
$$62 \over 60$$
$$16 \over 15$$
Q2.
Using a calculator, work out the answer to $${16 \over 15} \times {30 \over 32}$$.
$$480 \over 320$$
4
2
Correct answer: 1
Q3.
Izzy's calculator gives an answer as a fraction. What is the name of the key that should be pressed last on the Casio fx-991CW in order to convert this fraction to a decimal?
Correct Answer: EXE, exe, execute
Q4.
Using a calculator, match the decimal to the equivalent fraction.
Correct Answer:0.35,$$7 \over 20$$

$$7 \over 20$$

Correct Answer:0.894,$$447 \over 500$$

$$447 \over 500$$

Correct Answer:2.134,$$1067 \over 500$$

$$1067 \over 500$$

Correct Answer:2.413,$$2413 \over 1000$$

$$2413 \over 1000$$

Q5.
The format key on the Casio fx-991CW allows you to change between decimals, improper fractions and mixed numbers.
Correct answer: True
False
Q6.
Using your calculator, find the answer to $${21 \over 12} \times {2 \over 3}$$
1.16666
Correct answer: 1.166666667
1.1666666666666666666667
1.166666666666666666666666666666

Exit quiz

Download exit quiz

6 Questions

Q1.
Jacob uses his calculator to evaluate $$-3^2$$. What will the calculator display as the answer?
9 as this is the correct answer
9 as the calculator ignores the priority of operations
Correct answer: -9 as the calculator follows the priority of operations
-9 as this is the correct answer
Q2.
Working with fractions is always more accurate than using decimals.
True
Correct answer: False
Q3.
The calculator displays the decimal 1.234567891. Which of the following could this decimal be?
Correct answer: $$1.\dot{2}3456789\dot{1}$$
Correct answer: $$1.234567891\dot{4}$$
Correct answer: $$1.23456789\dot{1}$$
$$1.\dot{2}323456789\dot{1}$$
Q4.
Use your calculator to find the area of
An image in a quiz
Correct answer: $$5 \over 12$$ m$$^2$$
$$0.416$$ m$$^2$$
$$0.4166666667$$ m$$^2$$
$$16 \over 15$$ m$$^2$$
Q5.
Use your calculator to covert 0.6252 into a fraction. The numerator will be
Correct Answer: 1563
Q6.
Use your calculator to covert 0.0625 into a fraction. The denominator will be
Correct Answer: 16