
David W. answered 11/12/15
Tutor
4.7
(90)
Experienced Prof
Assign variables to the values the problem asks us to find.
Let x= How many votes were cast in the election
J = number of Jono’s votes
D = number of David’s votes
S = number of Salah’s votes
M = number of Damien’s votes
Now, translate:
“Jono received 40 votes more than 40% of the votes” means
J = 40 + (40/100)*x
“David received 10 votes more than 10% of the vote” means
D = 10 + (10/100)*x
“Salah received 20 votes less than 20% of the vote” means
S = -20 (20/100)*x
“Damien received the remaining 180 votes” means
M = 180
The total number of votes:
x = J + D + S + M
x = ( (40/100)x + 40 ) + ( (10/100)x + 10) + ( (20/100)x - 20 ) + 180
100x = 40x + 4000 + 10x + 1000 + 20x -2000 + 18000 [multiply by 100 to get rid of fractions]
30x = 21000 [collect terms]
x = 700 [divide each side by 3]
J = (40/100)(700)+40
J = 320
D = (10/100)(700) + 10
D = 80
S = (20/100)(700)-20
S = 120
M = 180
Checking (very important):
Is 320 + 80 + 120 + 180 = 700 ?
700 = 700 ? yes