Answer:
25
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