Q14.4.3). Two cars starts from two towns 400 miles apart and travel towards each other. They pass each other after 4 hours. Find the speed of each car if the difference bwtewwn their speed is 20 miles per hour.
+130511 OK
Let x be the rate of one car and let x + 20 be the rate of the other......
So the rate of the 1st car times the time it travels plus the rate of the second car times the time it travels equals the total distance covered by both cars (400 miles).....mathematically, we have
4x + 4(x + 20) = 400
4x + 4x = 80 = 400 simplify and subtract 80 from both sides
8x = 320 divide by 8 on both sides
x = 40mph ..... and that's the slower car's rate....and the faster car's rate = x + 20 = 40 + 20 = 60mph
+130511 OK
Let x be the rate of one car and let x + 20 be the rate of the other......
So the rate of the 1st car times the time it travels plus the rate of the second car times the time it travels equals the total distance covered by both cars (400 miles).....mathematically, we have
4x + 4(x + 20) = 400
4x + 4x = 80 = 400 simplify and subtract 80 from both sides
8x = 320 divide by 8 on both sides
x = 40mph ..... and that's the slower car's rate....and the faster car's rate = x + 20 = 40 + 20 = 60mph
