oe could be seen in calculation (120% is not M1 – something needs to have been done with it) \(\dfrac{5}{6}\) if used correctly could be an oe. Don’t award just for \(\dfrac{5}{6}\) seen
\(1.2x + 1.2 = x + 6\) or \(0.2x + 1.2 = 6\) or \(0.2x = 4.8\)
M1dep
oe but must have expanded brackets missing brackets need to be recovered
24
A1
Alternative method 2
\((x + 1) + \dfrac{(x + 1)}{5}\)
M1
oe
\(\dfrac{(x + 1)}{5} = 5\) or \((x + 1) = 25\)
M1dep
oe eg could be written as 20% of \((x + 1) = 5\)
24
A1
Additional guidance
20% = 5 or 100% = 25 \(1.2(x + 1) = x + 6\) then \(1.2x + 1 = x + 6\) would not gain second M mark
their \(5x\) − their \(4.2x = 28\) or \(0.8x = 28\)
M1dep
oe eg their \(5x\) = their \(4.2x + 28\) dep upon at least one of previous M marks earned
\(x = 35\)
A1
Alternative method 2
two numbers in the ratio 4 : 7
M1
correct increase by 25% and decrease by 40% calculations and comparison with 28
M1dep
If difference is not 28, then first numbers must be clearly rejected
second trial with correct calculations and comparison
M1dep
correct first trial means 2nd and 3rd M marks scored automatically
\(x = 35\)
A1
Additional guidance
Mark the better of their two versions if they try both methods.
In alt 2 … for the 2nd M1 (dep on 1st M1) … the % calculations must be correct. If the difference is not 28 they must reject them. Attempting another two % calculations is sufficient evidence of this.
In alt 2 … for the 3rd M1 (dep on the first two M1’s) … the difference must be closer than their first attempt. They can have more than one attempt at this so as to eventually score the 3rd M1. To score this mark they need to indicate clearly that this further attempt is better than their first attempt.
In alt 2 … if it isn’t clear in which order they have done their attempts (eg very untidy working written all over the page) and they do not indicate which is the better attempt, then they can score a maximum of 2 marks.
