Recurring decimals as fractions
3 exam-style questions. Answers and the mark for each step are on the last page.
- Question 1
Write each recurring decimal as a fraction in its simplest form.
(a)
(b)
- Question 2
(a) Use this fact to write as a fraction in its simplest form.
(b) Work out . Give your answer as a fraction in its simplest form.
- Question 3
(a) The digits a and b are non-zero. The decimal x = 0.ababab… repeats the two-digit block ab. The decimal y = 0.bababa… repeats the reversed block ba. Given x + y = 1 and x y = 3/11, find the two-digit integer ab. You must show your working.
Answers and marks
Question 1
(a)
- M1 Writing and subtracting.
- A1 The correct answer, .
(b)
- M1 Using and subtracting to get .
- A1 The correct answer, .
Question 2
(a)
- M1 Dividing by 10.
- A1 The correct answer, .
(b)
- P1 Writing .
- P1 Adding with a common denominator of 45.
- A1 .
Question 3
(a)
- P1 Establishing or an equivalent valid method.
- P1 Establishing or an equivalent valid method.
- A1 Correct answer: