Answer: 1 hour 20 minutes
Step-by-step explanation:
Given : The old machine could shred a truckload of paper in 4 hours.
Rate of work done by old machine = 
The new machine could shred the same truckload in 2 hours.
Rate of work done by new machine = 
Let 't' be the time taken by both of them working together , then we have the following equation:-
Since 1 hour = 60 minutes
Then, 
Hence, it will take 1 hour 20 minutes to shred the same truckload of paper if Ron runs both shredders at the same time.
Answer:
Approximately 76.5 mg.
Step-by-step explanation:
Given,
The initial quantity of the Bismuth-210, P = 233 mg,
Also, the rate of decay per day, r = 13 %
Thus, the quantity of the Bismuth-210 after 8 days would be,
3s + 4j = 360
1s + 3j = 220
This one we can solve using substitution, in that
s + 3j = 220 implies s = 220 - 3j (subtract 3j from each side).
Now substitute into the first equation:
3(220 - 3j) + 4j = 360. Solve for jackets.
660 - 9j + 4j = 360 [Distributive property]
660 - 5j = 360 [Add -9j + 4j]
Subtract 360 from each side, and add 5j to each side.
660 - 360 - 5j + 5j = 360 - 360 + 5j
300 = 5j
Divide each side by 5.
$60 = price of a jacket.
Three of these plus a shirt runs $220.
3(60) = 180
180 + s = 220
180 - 180 + s = 220 - 180 [Subtract 180 from each side]
s = 40
Now we double check.
3(40) + 4 (60) = 120 + 240 = 360. This satisfies the first equation.
We could check the second one too, but I'm satisfied.
The rate of ascent is also known as the slope. To find the slope, we will follow the steps below.
Step 1) Choose two points on the line
Point 1: (4, 500)
Point 2: (8, 1000)
Step 2) Use the slope formula to find the slope
m = (y2 - y1) / (x2 - x1)
m = (1000 - 500) / (8 - 4)
m = 500 / 4
m = 125 feet per minute
Hope this helps! :)
