Answer:
57 mph
Step-by-step explanation:
Let b represent Bob's speed on the trip. Then his time is ...
time = distance/speed
Bob's time = 230/b
Then John's speed is b+8, and his time is ...
John's time = 230/(b+8)
The difference of their times is 1/2 hour:
Bob's time - John's time = 1/2
230/b -230/(b+8) = 1/2 . . . substitute the expressions for time
460(b+8 -b) = b(b+8) . . . . . multiply by 2b(b+8)
b^2 +8b -3680 = 0 . . . . . . .put in standard form
(b +4)^2 -3696 = 0 . . . . . . . add 16-16 to complete the square
b = -4 +√3696 ≈ 56.795 . . . solve for positive b
Bob's drove about 57 mph on the trip.
Answer:The answer would be 3/12 and 5/12 Because 4×3 = 12
4 1/5a-2.2=
4 1/5a=4.2a So,
4.2a-2.2=2a
__________
-1 4/5a+3.8=
-1 4/5a=-1.8a So,
-1.8a+3.8=+5.6
I think that is it!
A
because it has used multiplicative property
Answer:
Step-by-step explanation:
Total number on the trip is 24
Let the number of girls be x
Then the boys are x + 8
So... x + x + 8 = 24
2x + 8 = 24.......... This is the equation
2x = 24 - 8
2x = 16
x = 16/2
x = 8
Number of girls = 8
And number of boys = x + 8
Which is = 8+8 = 16
