1MA0 Foundation November 2012 Paper 1 Q25
25 Here is a diagram of Jim’s garden.

Diagram NOT accurately drawn
Jim wants to cover his garden with grass seed to make a lawn.
Grass seed is sold in bags.
There is enough grass seed in each bag to cover 20 m\(^2\) of garden.
Each bag of grass seed costs £4.99
Work out the least cost of putting grass seed on Jim’s garden. (4)
| Working | Answer | Mark | Notes |
|---|---|---|---|
| \(\frac{9}{2} \times (12 + 18) = 135\) \(135 \div 20 = 6.75\) (=7 bags) \(7 \times 4.99\) OR \(18 \times 9 - \frac{1}{2}(6 \times 9) = 135\) \(135 \div 20 = 6.75\) (=7 bags) \(7 \times 4.99\) | 34.93 | 4 | M1 for \(\frac{9}{2} \times (12 + 18)\) or \(18 \times 9 - \frac{1}{2}(6 \times 9)\) or \(9 \times 12 + \frac{1}{2} \times (18 - 12) \times 9\) or 135 seen M1 (dep) for \(\text{`}135\text{'} \div 20\) or 6 or 7 seen M1 (dep on previous M1) for \(\text{`}6\text{'} \times 4.99\) or \(\text{`}7\text{'} \times 4.99\) A1 cao [SC: M1 for \((12 \times 9 + 6 \times 9) \div 20\) (= \(162 \div 20\)) or 8 or 9 seen M1 (dep) for \(\text{`}8\text{'} \times 4.99\) or \(\text{`}9\text{'} \times 4.99\) OR M1 for \((18 \times 9 - 6 \times 9) \div 20\) (= \(108 \div 20\)) or 5 or 6 seen M1 (dep) for \(\text{`}5\text{'} \times 4.99\) or \(\text{`}6\text{'} \times 4.99\)] |