Higher January 2020 Paper 2 Q3
3 Show that \(\;4\dfrac{2}{3} + 3\dfrac{4}{5} = 8\dfrac{7}{15}\)
(3)
| Scheme | Marks |
|---|---|
| \(\dfrac{14}{3}\,(+)\,\dfrac{19}{5}\) or \((4)\dfrac{10}{15}\,(+)(3)\dfrac{12}{15}\) or \((4)\dfrac{10a}{15a}\,(+)(3)\dfrac{12a}{15a}\) | M1 |
eg \(\dfrac{14 \times 5 + 19 \times 3}{3 \times 5}\) or \(\dfrac{70}{15} + \dfrac{57}{15}\) or \(\dfrac{70a}{15a} + \dfrac{57a}{15a}\) or \(4\dfrac{10}{15} + 3\dfrac{12}{15} = 7\dfrac{22}{15}\) oe | M1 |
\(\dfrac{70}{15} + \dfrac{57}{15} = \dfrac{127}{15} = 8\dfrac{7}{15}\) or \(7\dfrac{22}{15} = 8\dfrac{7}{15}\) or if shows \(8\dfrac{7}{15} = \dfrac{127}{15}\) at the beginning then show that the addition comes to \(\dfrac{127}{15}\) Working required Answer: Shown | A1 |
| (3) | |
| (3 marks) |
Notes
M1: for correct improper fractions or fractional part of numbers written correctly over a common denominator
M1: for correct fractions with a common denominator of 15 or a multiple of 15
A1: dep on M2 for a correct answer from fully correct working or shows that RHS = \(\dfrac{127}{15}\) and fully correct working shows LHS = \(\dfrac{127}{15}\)