Answer:
-2/3
Step-by-step explanation:
Answer:
- x +y = 500
- 0.65x +0.95y = 0.75(500)
- solution: (x, y) = (300, 200)
Step-by-step explanation:
A system of equations for the problem can be written using the two given relationships between quantities of brass alloys.
<h3>Setup</h3>
Let x and y represent the quantities in grams of the 65% and 90% alloys used, respectively. There are two relations given in the problem statement.
x + y = 500 . . . . . . quantity of new alloy needed
0.65x +0.90y = 0.75(500) . . . . . quantity of copper in the new alloy
These are the desired system of equations.
<h3>Solution</h3>
This problem does not ask for the solution, but it is easily found using substitution for x.
x = 500 -y
0.65(500 -y) +0.90y = 0.75(500)
(0.90 -0.65)y = 500(0.75 -0.65) . . . . . . subtract 0.65(500)
y = 500(0.10/0.25) = 200
x = 500 -200 = 300
300 grams of 65% copper and 200 grams of 90% copper are needed.
Hello!
The mean is the average of the numbers
To find the average you add them all up and divide the sum by the amount of numbers added
87 + 72 + 99 + 93 + 84 = 435
Divide the sum by the amount of numbers added
435 / 5 = 87
The answer is 87
Hope this helps!
Answer:
i say in blank one its 24cm
Step-by-step explanation: