How best can I approach the question below:
If Kwame had 3 cents more he would have twice as much as Ama. If he had 4 cents less, he would have the same amount.
How many cents does Kwame have?
e)none of the above
I solved it without using a (number thatAma has) in any equation. Here is how I did it (k being the number of Kwame's cents):
k + 3 = 2(k-4)
k + 3 = 2k - 8
k + 11 = 2k
11 = k
So Kwame has 11 cents. Using the simultaneous equations method you were using you can reach the same equation.
k + 3 = 2a
k - 4 = a
Using substituion and subbing the first into the second you can get to k + 3 = 2(k-4), as named earlier. Using elimination you can subtract the second from the first and get to 7 = a. Then sub the value for a into either equation to get k = 11.