Answer:
15 mL of the solution with 20% water will be needed.
Step-by-step explanation:
Use the inverse relationship
10 mL * (18-15)% = x mL * (20-18)%
x = 10 mL * (3/2) = 15 mL
ANSWER
The length of the rectangular field is 99 yards
EXPLANATION
Given information
The perimeter of a rectangle field is 372 yards
The width of the field is 87 yards
To find the length of the rectangular field, follow the steps below
Step 1: Write the formula for finding the perimeter of a rectangular field

Step 2: Substitute the given data into the formula in step 1

Hence, the length of the rectangular field is 99 yards
35 99/100 (35 wholes 99 over 100)
I find it convenient to look at the differences and the rate at which those differences are made up.
8. Jim is closing the $150 gap at the rate of $7.50 per week. He will catch up in
... 150/(7.5/week) = 20 weeks
9. At noon, the price of Stock A has increased by 0.05×3 = 0.15, so is now $15.90, which is $0.63 more than Stock B at that time. The prices are closing the gap at the rate of $0.05 +0.13 = $0.18 per hour, so will be the same after
... $0.63/($0.18/hour) = 3.5 hours . . . . after noon, at 3:30 pm
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You can also write and solve equations for the prices of the stocks. Or you can use a graphing calculator to tell you the solution. When equations are involved, I like to solve them the simplest possible way: let technology do it.
You are given the value at a time, and the rate of change of that value, so the equations are easily written in point-slope form. You will note that the common price at 3:30 pm (15.5 hours after midnight) is one that is not a whole number of cents. (That's usually OK for when trading stocks.)