Numeracy Foundation November 2017 Unit 1 Q4
4. Sophia designs jewellery.
She is working on the design of a bracelet.
Each link of the bracelet uses lengths of silver, 
.
(a) How many lengths of silver are needed for 3 links of the bracelet?
Circle your answer. [1]
Circle your answer. [1]
14 16 12 18 10
(b) Sophia thinks that she needs 6 lengths of silver for each extra link.
Explain why Sophia is not correct. [1]
Explain why Sophia is not correct. [1]
(c) Sophia uses 50 lengths of silver to make a bracelet.
How many links are there in this bracelet? [2]
How many links are there in this bracelet? [2]
| Scheme | Marks | Comments |
|---|---|---|
| 14 | B1 |
| Scheme | Marks | Comments |
|---|---|---|
| Correct explanation given E.g. ‘You add on 4 each time.’ ‘There are 2 lengths that are common.’ ‘There is some overlap.’ ‘Start with 6 but then add on 4 each time’ ‘Because after each link you need another 4 lengths of silver’ ‘Because she only needs 4’ ‘Because you don’t add on the middle links’ ‘If she uses 6 lengths of silver then she will have 2 spare for all but the first one’ ‘Needs 6 lengths of silver for only the 1st link’ | E1 |
| Scheme | Marks | Comments |
|---|---|---|
| Attempt to continue the sequence to 50 (6, 10, 14), 18, 22, 26, 30, 34, 38, 42, 46, 50 | M1 | Allow if clearly trying to create a linear sequence with difference of 4. (Allow no more than 2 errors) Award M1 for correct diagram with 12 links drawn An answer of 12 earns both marks |
12 | A1 | Alternative method 1 (50 – 2) ÷ 4 M1 12 A1 Alternative method 2 1 + (50 – 6) ÷ 4 M1 12 A1 Accept embedded answers. Award SC1 for an evaluated answer from an incomplete method (50 - lengths of silver) ÷ 4 Eg (50-10) ÷ 4 = 10 or (50-6) ÷ 4 = 11 |