Answer:
30 mph
Step-by-step explanation:
Let the morning speed be represented by s.
Then the total distance drivern is 310 mi and this is equal to
5s + 4(s + 10):
5s + 4s + 40 = 310, or
9s = 270
Solving for s, we get s = 270/9 = 30
Then s + 10 = 40
He drove 30 mph in the morning and 40 mph in the afternoon.
Check: (30 mph)(5 hrs) + (40 mph)(4 hrs) = 310 miles. CORRECT
Answer:
380 + 6 + 14
Step-by-step explanation:
The sum of 386 and 14 is 386 + 14 = 400.
To find which stategy he used, we find the results of each sum, and it has to be 400.
380 + 6 + 14
380 + 6 + 14 = 386 + 14 = 400
So this is the strategy that he could have used.
380 + 14 + 14
380 + 14 + 14 = 394 + 14 = 408
Result different of 400, which means that this was not the strategy
386 + 10 + 4 + 14
386 + 10 + 4 + 14 = 386 + 14 + 14 = 408
Result different of 400, which means that this was not the strategy
386 + 14 + 80 + 6
386 + 14 + 80 + 6 = 400 + 86 = 486
Result different of 400, which means that this was not the strategy
Answer:
fact
Step-by-step explanation:
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