|
Question 1137112: Hello, I need help setting up the equation. The problem is:
In 16 years Dana will be five times older than she was four years ago. In how many years will Dana celebrate her 16th birthday?
D=Dana
(D x 5) - 4 = 16
does not seem correct. Thanks for your help.
Answer by Theo(13342)   (Show Source):
You can put this solution on YOUR website! let x equal her age today.
in 16 years, she will be 5 times older than she was 4 years ago.
the equation for that would be x + 16 = 5 * (x - 4) + (x - 4).
simplify that equation to get x + 16 = 6 * (x - 4).
that means she will be 6 times as old as she was 4 years ago.
simplify that equation to get x + 16 = 6 * x - 24.
add 24 to both sides of this equation and subtract x from both sides of this equation to get 40 = 5 * x.
solve for x to get x = 40 / 5 = 8.
she is 8 years old today.
4 years ago she was 4 years old.
16 years from now, she will be 24 years old.
24 years old / 4 = 6.
that means that she will be 6 times 4 years old in 16 years.
if she will be 6 times 4 years old in 16 years, subtract 4 from that and you will get she is 20 years older than 4 years old which means she is 5 times older than she was 4 years ago.
24 / 4 = 6 times as old.
(24 - 4) / 4 = 20 / 4 = 5 times older.
if this is not the answer you are looking for, then send me an email and i'll revise the answer from her being 5 times older to her being 5 times as old.
there is a difference between the two statements and it's a very important difference.
|
|
|
| |
