1MA0 Foundation June 2014 Paper 1 Q10
10 You can use these rules to change temperatures from \(^\circ\)C to \(^\circ\)F.
| approximate rule |
|---|
| Multiply the \(^\circ\)C temperature by 2 and then add 30 |
| exact rule |
|---|
| Multiply the \(^\circ\)C temperature by 1.8 and then add 32 |
Amy uses the approximate rule to change 20\(^\circ\)C to \(^\circ\)F.
Dan uses the exact rule to change 20\(^\circ\)C to \(^\circ\)F.
(a) Work out the difference between Amy’s result and Dan’s result. (4)
Jade uses the approximate rule to change a temperature from \(^\circ\)C to \(^\circ\)F.
The result is 110\(^\circ\)F.
(b) What \(^\circ\)C temperature did Jade change to \(^\circ\)F? (3)
| Answer | Mark | Notes |
|---|---|---|
| 2 | 4 | M1 for 20 × 2 + 30 (=70) M1 for 20 × 1.8 + 32 (=68) M1 (dep on M1) for “70” – “68” A1 cao |
| Answer | Mark | Notes |
|---|---|---|
| 40 | 3 | M1 for 110 – 30 ÷ 2 or 110 = ? × 2 + 30 or 110 – 30 or ÷ 2 seen as second operation M1 for “(110 – 30)” ÷ 2 A1 cao NB accept reverse flowcharts for inverse operations SC if exact rule used: B2 for “(110 – 32)” ÷ 1.8 |