During a 4th of July weekend, 32 vehicles became trapped on the Sunshine Skyway Bridge while it was being repaved. A recent city ordinance decreed that only cars with 4 wheels and trucks with six wheels could be on the bridge at any given time. If there were 148 tires that needed to be replaced to due to damage, how many cars and trucks were involved in the incident?

i got this far:
c = number of cars; t = number of trucks

c + t = 32
4c + 6t = 148

Question

During a 4th of July weekend, 32 vehicles became trapped on the Sunshine Skyway Bridge while it was being repaved. A recent city ordinance decreed that only cars with 4 wheels and trucks with six wheels could be on the bridge at any given time. If there were 148 tires that needed to be replaced to due to damage, how many cars and trucks were involved in the incident? 


i got this far:
c = number of cars; t = number of trucks

c + t = 32
4c + 6t = 148

anonymous · Answer

i solved for t and got 10 but when i solve for c i get 14 and that doesnt add upto 32 :(

anonymous · Answer

Could you please shoe me the steps you did?

anonymous · Answer

if you found dat c=10, den from first equation.......... t must be 22, where did you get 14 from?

anonymous · Answer

wait sorry, you cant get t as 10, show us ur working

anonymous · Answer

for t...

4(32-t) +6t = 148
128 -4t+6t = 148
2t = 20 
t =10

then for c...

4(10) + 6(32-c) = 148
40 + 192 - 6c = 148
232 -6c = 148
-6c = -84
6c = 84
c =14

anonymous · Answer

ive checked over it a bunch of times and its not working

anonymous · Answer

after you get t
substitute it into first equation

anonymous · Answer

thats wat i did @Tushara

anonymous · Answer

t=10
then all you do is
using c+t=32
c+10=32
c=22

dont do the long process

anonymous · Answer

t is correct! Well done!
Now we can use the 1st equation instead of the 2nd:
c + t = 32
c+10=32
So, what do we get for c?

anonymous · Answer

@rafabc02....you'd get 22 for c but why doesnt it work in the second equation??

anonymous · Answer

what you did was : 4(10)
it is 4c
so you cant substitute the t value into c
c is not 10

anonymous · Answer

OHHHH

anonymous · Answer

It does work. Let's see:
t=10, c=22. So:
4c + 6t = 148
4*22+6*10=88+60=148 
:)

anonymous · Answer

thanks soo much @Tushara

anonymous · Answer

yes :) np

anonymous · Answer

wow.....tht was an epic fail...i feel stupid now :P

anonymous · Answer

haha silly mistakes happen

anonymous · Answer

haha yea

anonymous · Answer

You don't have to feel stupid! Everyone makes mistakes!
No worries!

anonymous · Answer

alright guys...thanks so much for the help....makin my life easier :D .... bye! :)

anonymous · Answer

You are welcome! Have a wonderful day!

anonymous · Answer

aite u too!

anonymous · Answer

Thanks!