Martina leaves home at 9am, bicycling at a rate of 24 mi/h. Two hours later, sam leaves driving at the rate of 48 mi/h. At what time will Sam catchup to Martina?
Would this be: 24X+48(X-2)=time?
2007-01-07 09:27:17 · 4 answers · asked by bill_scott_2004 1 in Science & Mathematics ➔ Mathematics
Let x = the time that passes after Sam starts going. That means that after x hours, Sam will have travelled 48x miles. Sam starts driving at 11am.
Martina bikes 2 hours before Sam starts going. That means Martina has biked 2 * 24 = 48 miles already before Sam started going. Martina's total distance will be 48 + 24x.
What time will they catch up? 48 + 24x = 48x. Solve for x. This is how long in hours it will take for Sam and Martina to catch up.
48 + 24x = 48x
48 + 24x - 24x = 48x - 24x
48 = 24x
x = 2 hours.
It will take 2 hours for Sam and Martina to catch up to each other. By then, it will be 11am + 2 hours = 13 = 1pm.
2007-01-07 09:51:37 · answer #1 · answered by Wendy C 2 · 0⤊ 0⤋
rate*time = distance You are looking for when the distances are equal. Let x be the number of hours travelled
24x = 48(x-2)
24x = 48x - 96
96 = 24x
x = 4
So they meet up at 1:00 pm. Doesn't hurt to check, though.
Martina travelled 4 hours at 24 mph, which means she travelled 96 miles.
Sam travelled two hours less, so 2 hours at 48 mph, which is also 96 miles.
2007-01-07 17:39:37 · answer #2 · answered by hunneebee22 4 · 1⤊ 0⤋
Sam catches up when they travel the same distance.
when Rsam X Tsam = Rmartina X Tmartina
2007-01-07 17:32:45 · answer #3 · answered by davidosterberg1 6 · 0⤊ 0⤋
24 T = 48 (T-2).
2007-01-07 17:31:43 · answer #4 · answered by gianlino 7 · 0⤊ 0⤋