Let the speed of the boat be x
so going against the current the speed is x-7
going with the current the speed is x+7
let the distance be d
time = distance / speed
time to go against the current = d/(x-7)
time to go with the current = d/(x+7)
time going against the current is 3 times going <span>with the current
</span>
d/(x-7) = 3d/(x+7)
⇒⇒⇒ divide by d
1/(x-7)
= 3/(x+7)
x+7
= 3(x-7)
x+7 = 3x - 21
2x = 28
x = 14
So, the speed of the boat in still water is = 14 mph
1a. 5/10 can be simplified to 1/2. (5 divided by 5 is one, 10 divided by 5 is 2.)
1b. 9/12 can be simplified to 3/4. (9 divided by 3 is 3, 12 divided by 3 is 4.)
1c. 12/18 can be simplified to 2/3. (12 divided by 6 is 2, 18 divided by 6 is 3.)
1d. 9/24 can be simplified to 3/8. (9 divided by 3 is 3, 24 divided by 3 is 8.)
1e. 27/90 can be simplified to 3/10. (27 divided by 9 is 3, 90 divided by 9 is 10.)
1f. 40/48 can be simplified to 5/6. (40 divided by 8 is 5, 48 divided by 8 is 6.)
Step-by-step explanation:
///////hope it helps:)
Answer:
How long will it take a plane to fly 310 miles at 124 miles per hour?
A.) 1.5h
B.) 2h
<u>C.) 2.5h
</u>
D.) 3h
Step-by-step explanation:
