Two Math Word Problems! Help!!!?

Question

On the first of a 415-mile car trip I averaged 60 miles per hour. On the second part I averaged 70 miles per hour. My total driving time was 6 hours and 15 minutes. Find the amount of time at each speed. Show all the work.


Also,

Our job is to estimate the height of the Washington Monument. We measered the shadow cast by the monument and found it to be 42.25 meters long. Then we measured the shadow cast by a 1.8 meter tall park ranger standing near the monument and found it to be 0.45 meters long. Estimate the height of the Washington Monument. Show all the work.


Please help me...I'm no good at word problems...ty very much!

Answer 1

Two different equations needed with 2 unknowns
x + y = 6.25
60x + 70y = 415

Taking the first x = 6.25 - y

Substituting that into the second
60 (6.25 - y) + 70y = 415
375 - 60 y + 70y = 415
375 + 10y = 415
10y = 415 - 375
10y = 40
y = 4

So 4 hours at 70 mph and 2 hours 15 minutes at 60.
280 + 135
_______________________

X is to 42.25 as 1.8 is to 0.45
or
X/42.25 = 1.8/0.45
X = (42.25 * 1.8)/0.45
X = 76.05/0.45
X = 169

Answer 2

ok
#1 you spent 4:00 hours going 70
and 2:15 going 60
#2 169m tall

Work
#1 you just keep plugging in numbers until it fits (i would recomend throwing in some random #'s first and then showing your work with the right answer to make it look more realistic. its just guess and check
i did it in excel so it was easy
(70x)+(60y)=415 plug in 4 for x and 2.25(which is 2:15 in hours) for y


#2 you just take the shadows(42.25 and .45) and multiply those together then you divide by the height of the park ranger(1.8
this gives u 169m

Answer 3

1) distance = speed * time

First part, time = x min
Second part, time = 6hrs 15 mins - x mins = 375 - x mins

Therefore, 415 miles = 60miles/hr*xmins + 70miles/hr*(375-x)mins

Convert the miles/hr to miles/min and substitute in above eqn, you will get the value of x which is the time taken for first part of trip, and (375-x) is time taken for second part. The answer obtained will be in minutes.

2) Washington monument height/shadow = x/42.25
park ranger height/shadow=1.8/0.45

Equating both, we get:
x/42.25 = 1.8/0.45
x = 169metres = height of washington monument

Answer 4

The equations you've for the 2d subject are staggering. For the first one assign x, y and z values for the variety of 1s 5s and 10s as those are the variables you do not comprehend. each and every sentence is an equation. the first is 1x + 5y +10z = ninety six the 2d is y + z = x +a million or rearranged -x + y + z = a million The third is x + y + z = 23 Now you in basic terms ought to sparkling up for x, y and z. desire this helps.

Answer 5

x = miles(60)
y = miles(70)

450 = x+y
6.25 = 60x + 70x

x/42.25 = 1.8/0.45

Answer 6

Sorry, I'm no good at physics. I barely getting a C.

Answer 7

Poncho Rio looks about right. go with him :)