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.
A meter = 10000 cm
30cm/1m
30/10000
=0.003
x100 (for the percent)
=0.3%
Answer:
The price of the kilogram of cookies is $ 1.8
Step-by-step explanation:
Call x the price of the kilogram of candy and call y the price of kilogram of cookies
Then we know that
We also know that the price of kilogram of cookies is 1.40 dollars cheaper than the kilogram of candy
So
We solve this equation for x and then we substitute it in the first equation.
How much did he have in the first place ?
