Answer:
A
Step-by-step explanation:
I just took the test and i got it correct! :)
8 a.m. to 1 p.m. = 5 hrs
so the temperature changed -3/5 degrees per hr for 5 hrs...
-3/5 * 5 = -15/5 = -3.....so in total, the temperature changed by 3 degrees....it went down 3 degrees
Answer: rate of train A = 120 km/h
rate of train B = 101 km/h
Step-by-step explanation:
Let x = the speed of train A
Let y = the speed of train B
One train travels 19 km/h slower than the other. Let train B be the slower train. Therefore,
x = y + 19 - - - - - - - - - -1
Recall
Speed = distance/time
Distance = speed × time
If they meet in 3 hours, it means that train A has travelled a distance of
x × 3 = 3x km
And train B has travelled a distance of y × 3 = 3y km
Train A and Train B were 663 kilometers apart when they left their respective destinations. They left at the same time and travelled towards each other. This means that if they meet in 3hours time, they must have covered a total of 663 km. Therefore,
3x + 3y = 663 - - - - - - - - - 2
Substituting x = y + 19 into equation 2, it becomes
3(y + 19) + 3y = 663
3y + 57 + 3y = 663
6y + 57 = 663
6y = 663 - 57 = 606
y = 606/6 = 101 km/h
x = y + 19 = 101 + 19
x = 120 km/h
Based on the number of hours in the work week, the cost of the laborers and masons, worth of the materials and the profit, the estimated cost of the job can be written as a mathematical statement of A. 3 x $15 x 40 + 4 x $25 x 40 + $3,268 + $700 = $
The total estimated cost is $9,768
<h3>What is the total estimated cost?</h3>
The total estimated cost of the job can be found by the formula:
= (Number of laborers needed x Cost of laborers x Number of hours in work week) + (Number of masons x cost of masons x number of hours in work week) + materials worth + Required profit
The total estimated cost is therefore:
= (3 x $15 x 40) + (4 x $25 x 40) + $3,268 + $700
= 1,800 + 4,000 + 3,268 + 700
= $9,768
Find out more on total estimated cost at brainly.com/question/20950074.
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