5 (a) Emma saves £1 coins and £2 coins.
She has twice as many £1 coins as £2 coins.
She has saved exactly £100
How many £2 coins does she have?
12 marks
Answer

25

Step-by-step explanation:

25 2 euro coins*2=50

50 1 euro coins*1=50

50+50=100

25

Step-by-step explanation:

We can have a set of equations for this. Let x be the number of 1 pound coins and y be the number of 2 pound coins.

We can set an equation like this:

Since she has twice as many 1 pound than 2 pound coins, we can set this equation:

x=2y

Since the worth of the coins add up to 100:

(1 pound)*x+(2 pounds)*y=100pounds

x+2y=100

We can substitute x=2y

2y+2y=100

y=25

Therefore we have 25 2 pound coins