IDNStudy.com, ang iyong gabay para sa mga sagot ng komunidad at eksperto. Ang aming mga eksperto ay nagbibigay ng mabilis at eksaktong sagot upang tulungan kang maunawaan at malutas ang anumang problema.
Sagot :
Answer:
The present age of Robie's father is 40 and the present age of Robie is 10.
Step-by-step explanation:
If Robie's father is 4 times as old as Robie and after 5 years he will be 3 times as old as Robie, we have to write this in expression form to further solve. Try putting the father as f and Robie as r. So if f is 4 times r and after 5 years f is 3 time r, then add the first side with f is 4 times r and since 5 years after affects both variables add 5 to both variables in the second side as r becomes a third of f. Written in expression, we have [tex]f=4r; r+5=\frac13(f+5)[/tex]. Having this we can solve by substitution.
To solve by substitution, rewrite the equation (if necessary), substitute the values for variables, and give the answer.
Let us start solving by:
(1) Rewriting the equation (it is necessary right now)
[tex]f=4r; r+5=\frac13(f+5) \\ f=4r; r+5=\frac13f + \frac{5}{3} [/tex]
(2) Substitute the values for variables
(2a) Substitute for f
[tex]f = 4r \\ r + 5 = \frac{1}3f + \frac53 \\ r + 5 = \frac{1}34r + \frac53 \\ r + 5 = \frac{4}3r + \frac53 \\ r + 5 + \frac{ - 4}{3} = \frac{4}3r + \frac53 + \frac{ - 4}{3} \\ \frac{ - 1}{3} r + 5 = \frac{5}{3} \\ \frac{ - 1}{3}r + 5 - 5 = \frac53 - 5 \\ \frac{ - 1}{3} r = \frac{ - 10}{3} \\ \frac{ \frac{ - 1}{3} r}{ \frac{ - 1}{3} } = \frac{ \frac{ - 10}{3} }{ \frac{ - 1}{3} } \\ r = 10[/tex]
(2b) Subsitute for r
[tex]r = 10 \\ f = 4r \\ f = (4)(10) \\ f = 40[/tex]
(3) Give the answer
f (The present age of the father) is 40 and r (the present age of Robie) is 10.
Salamat sa iyong kontribusyon. Patuloy na magbahagi ng iyong karanasan at kaalaman. Ang iyong ambag ay napakahalaga sa aming komunidad. May mga katanungan ka? Ang IDNStudy.com ang may sagot. Bisitahin kami palagi para sa pinakabagong impormasyon.