Answer:
(A)129 Pounds
Step-by-step explanation:
Let x be the number of 23% zink alloy
Therefore:
Since the total result is 516 pounds
The number of pounds of 42% zink alloy =516-x pounds
We then have the resulting equation:
0.23x+0.42(516-x)=0.3725*516
0.23x+216.72-0.42x=192.21
Colect like terms
0.23x-0.42x=192.21-216.72
-0.19x=-24.51
Divide both sides by 129
x=129 pounds
Therefore, the number of pounds of 23% zink alloy that must be mixed is 129 pounds.
The oldest son will get $370, the middle will get $220 and the youngest will get $185.
Step-by-step explanation:
Given,
Total amount to be split = $775
Let,
Oldest son's share = x
Middle son's share = y
Youngest son's share = z
According to given statement;
x+y+z=775 Eqn 1
the oldest gets twice as much as the youngest
x = 2z Eqn 2
the middle son gets $35 more than the youngest
y = z+35 Eqn 3
Putting value of x and y from Eqn 2 and 3 in Eqn 1

Dividing both sides by 4

Putting z=185 in Eqn 2

Putting z=185 in Eqn 3

The oldest son will get $370, the middle will get $220 and the youngest will get $185.
Keywords: linear equation, substitution method
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AMOUNT OF GALLONS MULTIPLIED BY 8 :)
Answer:8,400 miles
Step-by-step explanation: You would do 2,100•4 because you are driving 2,100 miles a week and there are 4 weeks you would have to times the amount of miles by how many weeks