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?
a)4
b)7
c)11
d)14
e)none of the above
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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?
a)4
b)7
c)11
d)14
e)none of the above
LetQuote:
Originally Posted by KayPee
be the amount that Ama has, now rewrite what you are told in terms of
CB
Let a be what Ama has and b be what Kwame has
b + 3 = 2a
b - 4= 2a
a = b + (3/2) = a
Substituting a into equation 2
b-4 = b + 3
I am stuck and the equation doesn’t sound ok
Where did I go wrong?
See the change in red aboveQuote:
Originally Posted by KayPee
CB
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.
Simply subtract 2nd equation from 1st: k - k + 3 - (-4) = 2a - aQuote:
Originally Posted by Ross137
So 7 = a
Yep - that's what I meant by elimination (Nod)