Answer:
The value of x is 3.
Step-by-step explanation:
Matthew earned 7500 of 15000, that is, 1/2.
Rate of 5:2:x, with number 5 corresponding to Matthew, mean that his fraction of the earnings is given by:
[tex]\frac{5}{5 + 2 + x} = \frac{5}{7 + x}[/tex]
Since he earned 1/2 of the total:
We have that 5/(7+x) = 1/2. So we use this to find x.
[tex]\frac{5}{7 + x} = \frac{1}{2}[/tex]
Applying cross multiplication:
[tex]7 + x = 10[/tex]
[tex]x = 10 - 7[/tex]
[tex]x = 3[/tex]
The value of x is 3.