Foundation June 2022 Paper 3 Q19
19 There are 400 counters in a box.
The counters are red or yellow or green.
\(\dfrac{3}{8}\) of the counters are red.
82 of the counters are yellow.
What percentage of the counters are green? (4)
| Answer | Mark | Mark scheme |
|---|---|---|
| 42 | P1 | for process to find number of red counters, eg \(400 \div 8 \times 3\ (= 150)\) or process to convert both to percentages: \(3/8\) as 37.5 and \(82/400\) as 20.5 or process to convert both to fractions with common denominator: eg \(3/8\) as \(75/200\) and \(82/400\) as \(41/200\) oe |
| P1 | for process to find number of green counters, eg \(400 - \text{``}150\text{''} - 82\ (= 168)\) or process to find the percentage of red and yellow counters eg \(\text{``}37.5\text{''} + \text{``}20.5\text{''}\ (= 58)\) or \((\text{``}150\text{''} + 82) \div 400 \times 100\ (= 58)\) | |
| P1 | for complete process to find the percentage of counters that are green, eg \(\text{``}168\text{''} \div 400 \times 100\) or \(100 - (37.5 + 20.5)\) or \(100 - \text{``}58\text{''}\) | |
| A1 | cao |
Additional guidance
NB could use other decimals eg 0.375, 0.205 or % or fractions