IDNStudy.com, ang perpektong platform para magtanong at makakuha ng maaasahang mga sagot. Ang aming komunidad ay nagbibigay ng eksaktong sagot upang matulungan kang maunawaan at malutas ang anumang problema.

The sum of robin's age and bruno's age is 45. Seven years ago robin was 16 years more than one-half as old as bruno was then. How old is robin now?

Sagot :

i'm not really sure if my answer is correct but i think the answer is 23 I guess :)
~hope it helped :)
Present ages:
Robin: x
Bruno: y

x + y = 45
      y = 45 - x

Ages seven years ago:
Robin: x - 7
Bruno:  45 - x - 7   or    38-x

Equation:
x - 7 = ¹/₂ (38-x) + 16
x  =  19 - ¹/₂ x + 16 + 7
x + ¹/₂ x = 19 + 16 + 7
x + ¹/₂ x = 42

LCD: 2
(2)x + (2) ¹/₂ x = (2) 42
2x + x = 84
3x = 84
3x/3 = 84/3
x = 28

ANSWER:  Robin is 28 years old now.

Present ages:
Robin: x = 28 years old
Bruno: 45 - x = 45 - 28 = 17 years old

Check:
28 + 17 = 45
45 = 45   √