Respuesta :
Answer:
A= 30 years old
B= 20 years old
Step-by-step explanation:
Let the present age of A be x years old.
Since the sum of the present ages of A and B is 60 years,
present age of B= (60-x) years old
In 5 years
A= x +5
B= 60 -x +5= 65-x
Since the ratio of A:B= 4:3,
A would represent 4 units and B would represent 3 units.
Thus [tex]\frac{3}{4}[/tex]A=B
[tex]\frac{3}{4}[/tex](x+5)= 65 -x
[tex] \frac{3}{4} x + \frac{15}{4} = 65 - x \\ \frac{3}{4} x + x = 65 - \frac{15}{4} \\ \frac{7}{4} x = 61.25 \\ 7x = 61.25 \times 4 \\ 7x = 245 \\ x = 245 \div 7 \\ x = 35[/tex]
Thus, present age of A
= x
= 35 years old
present age of B
= 60 -x
= 60 -35
= 25 years old
5 years ago
A= 35 -5= 30 years old
B= 25 -5= 20 years old
* under the section in 5 years, [tex]\frac{3}{4} A=B[/tex] because both would be equal to 3 units each. Since B is 3 units and A is 4 units, in order to make both value the same, we divide the 4 units of A by 4 then multiply by 3 to get 3 units. Thus, [tex]\frac{3}{4}[/tex] of A is equal to B.