Question 323329
Let a = Ann's present age
Let b = Bill's present age
:
Write an equation for each statement:
:
"Ann's age is seven-tenths of Bill's age."
a = {{{7/10}}}b
or
a = .7b
:
"In 4 years Ann's age will be eight-elevenths of Bill's age."
a + 4 = {{{8/11}}}(b + 4)
Multiply both sides by 11
11(a+4) = 8(b + 4)
11a + 44 = 8b + 32
11a = 8b + 32 - 44
11a = 8b - 12
Replace a with .7b
11(.7b) = 8b -12
7.7b = 8b - 12
12 = 8b - 7.7b
12 = .3b
b = {{{12/.3}}}
b = 40 is Bills age
;
:
Find a
a = .7(40)
a = 28 is Anns age
check solution in the statement:
"In 4 years Ann's age will be eight-elevenths of Bill's age."
28 + 4 = {{{8/11}}}(40+4)
32 = {{{8/11}}}*44
32 = 32