1MA0 Higher June 2014 Paper 2 Q18
18 Katie invests £200 in a savings account for 2 years.
The account pays compound interest at an annual rate of
3.3% for the first year
1.5% for the second year
(a) Work out the total amount of money in Katie’s account at the end of 2 years. (3)
Katie travels to work by train.
The cost of her weekly train ticket increases by 12.5% to £225
Katie’s weekly pay increases by 5% to £535.50
*(b) Compare the increase in the amount of money Katie has to pay for her weekly train ticket with the increase in her weekly pay. (3)
| Answer | Mark | Notes |
|---|---|---|
| 209.69 or 209.70 | 3 | M1 for \(200 \times \dfrac{3.3}{100}\) oe or \(200 \times 1.033\) or 6.6(0) or 206.6(0) M1 (dep) for \((200 + \text{``}6.6\text{''}) \times \dfrac{1.5}{100}\) oe or \(200 \times 1.033 \times 1.015\) oe or 3.099 or 3.09 or 3.10 or an answer between 209.69 and 209.7 A1 for 209.69 or 209.7(0) |
| Answer | Mark | Notes |
|---|---|---|
| Comparison | 3 | M1 for method to find cost of tickets before increase eg \(\dfrac{225}{1.125}\) (=200) oe or \(\dfrac{225}{112.5} \times 12.5\) oe or pay before increase, \(\dfrac{535.50}{1.05}\) (=510) oe A1 for 25 (train) and 25.5(0) (pay) or 310 and 310.5(0) C1 (dep on M1) ft for statement comparing rises leading to conclusion based on two comparable amounts eg pay increase greater than train increase |
Working
| Train | Pay | Diff | |
|---|---|---|---|
| Old | 200 | 510 | 310 |
| New | 225 | 535.50 | 310.50 |
| Diff | 25 | 25.50 | 50p |