I need help with my Algebra word problems?
1) Two airplanes leave at the same time from airports that are 880 miles apart and travel toward each other. If one plane travels 126 mph faster than the other and they pass each other in 2 hours, how fast is each plane traveling?
2) A jet travels from Chicago to Kansas City at a speed of 440 knots. If it takes a plane 3 hours longer to fly from Kansas City to Chicago when flying at a speed of 110 knots, what is the air distance between the two cities?
3) Karen saves her change and has dimes, nickels, and pennies totaling $4.52. If there is 1 more dime than three times the number of nickels and 10 more pennies tahn nickels, how many of each type of coin are there?
4) John and Jim are going on a bike ride. On the trip to Mill Park, they ride at an average of 8 mph on a route that is 4 mile less than the route on the return trip. They travel 7 mph on the return trip. If it takes them 1 hour longer to return than to go, how much total time do they spend riding their bicycles?
June 1st, 2009 at 4:38 am
1.Distance (s)= 880 miles; planeA speed (Va) ; planeB speed (Vb)= Va+126; time(t)=2
Va*2+ Vb*2=880
Va*2 + (Va+126)*2=880
Va=157miles/hr
Vb=283miles/hr
2.V1= 440 knots, V2= 110 Knots; time(t); same distance
440 * t=110 * (t+3)
t= 1 hour
Distance = 440*1= 440
3.Pennies (p) = .01 ; Nickels (n) = .05 ; Dime (n) = .1; total = 4.52
P = 10+n
3n=1+d ; d= 3n-1
P*.1 + n * .05 + d * .01 = 4.52
Substitute and solve for n and plug back in to p and d
4.Bike Route 1 Avg Speed = 8mph; Distance1 = S; Bike Route 2 Avg Speed = 7mph; Distance2 = s+4;
S = (8mph)*(t)
S +4 = (7mph)*(t+1); s = 7t + 7 – 4; s = 7t + 3
Substitute
7t + 3 = 8t; = t = 3
So it takes them 3hrs one way and 4 hrs the other way = total travel 7hrs.
This should help.