Answered

Makakuha ng mabilis at maaasahang mga sagot sa iyong mga tanong sa IDNStudy.com. Magtanong at makatanggap ng eksaktong sagot mula sa aming mga bihasang miyembro ng komunidad.

carol is five times as old as her brother. she will be three times as old as her brother in two years . how old is carol?

Sagot :

Kikoriotsoidn
Let 'x' be Carol's age at present
     'y' be her brother's age at present
Two years from now:
Let 'x+2' be Carol's age two years from now
     'y+2' be her brother's age two years from now
---------------------------
Carol is five times as old as her brother
x = 5y   ------equation 1
--------------------------
she will be three times as old as her brother in two years
x + 2 = 3(y+2)   ----equation 2
------------------------
From equation 2:
x+2= 3(y+2)
x+2 = 3y + 6
x = 3y + 6 - 2
x = 3y + 4   -----equation 3
-----------------------
Substitute equation 3 to equation 1
x = 5y
3y + 4 = 5y
5y - 3y = 4
2y = 4
y = 2
---------------------
Substitute y=2 to equation 1
x = 5y
x = 5(2)
x = 10
---------------------
Therefore at present,Carol is 10 years old while her brother is 2 years old.