Question 834127
Write an equation for each statement
:
Pete, Mike and John are cousins.
 Pete's age is one-third of Mike's age
p = {{{1/3}}}*m
 and John's age is five years older than Mike's.
j = m+5
 If the sum of the ages of the cousins is 40,
p + m + j = 40
Replace p and j from the 1st and 2nd equations, find m
{{{1/3}}}m + m + (m+5) = 40
{{{1/3}}}m + 2m = 40 - 5
{{{1/3}}}m + 2m = 35
multiply by 3 to get rid of the fraction
 m + 6m = 105
 7m = 105
m = 105/7
m = 15 is Mikes age
then
p = {{{1/3}}}*15
p = 5 is Pete's age
and
j = 15 + 5
j = 20 is John's
:
Note that the three ages do indeed, add up to 40