SOLUTION: mary is running to school. She leaves home at 8am trotting at a speed of 7mph. Her little lamb leaves home at at 8:15am running at a speed of 12 mph. What time of day will the lamb

Question 100087: mary is running to school. She leaves home at 8am trotting at a speed of 7mph. Her little lamb leaves home at at 8:15am running at a speed of 12 mph. What time of day will the lamb catch mary? Round your answer to the nearest minute. (Example 1027 am)
Found 2 solutions by ankor@dixie-net.com, checkley71:
Answer by ankor@dixie-net.com(22740) (Show Source): You can put this solution on YOUR website!
She leaves home at 8am trotting at a speed of 7mph. Her little lamb leaves home at at 8:15am running at a speed of 12 mph. What time of day will the lamb catch Mary? Round your answer to the nearest minute.
:
Let t = time from 8am L catches M
Then
(t-(1/4)) = L,s time running. Changed 15 min to hrs: 15/60 = 1/4)
:
When L catches M, they will have traveled the same distance.
Make a simple equation from this fact.
:
Dist = speed * time
:
7t = 12(t-(1/4))
:
7t = 12t - 3
:
7t - 12t = -3
:
-5t = -3
:
t = -3/-5
:
t = +.6 hrs; .6 * 60 = 36 min
:
L catches M at 8:36 am
:
:
Check solution by seeing if the distances are equal
M: 7 * .6 = 4.2 mi
L: 12(.6-.25) = 4.2 mi also
Answer by checkley71(8403) (Show Source): You can put this solution on YOUR website!
7T=12(T-.25)
7T=127-3
7T-12T=-3
-5T=-3
T=-3/-5
T=3/5=.6 ANSWER
PROOF
7*.6=12(.6-.25)
4.2=12*.35
4.2=4.2

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