Step-by-step explanation:
If x is the mass of 30% copper alloy, and y is the mass of 65% copper alloy, then:
x + y = 80
0.30x + 0.65y = 0.51(80)
Solving the system of equations using substitution:
0.30x + 0.65(80 − x) = 0.51(80)
0.30x + 52 − 0.65x = 40.8
11.2 = 0.35x
x = 32
y = 80 − x
y = 48
The metalworker needs 32 kg of 30% copper alloy and 48 kg of 65% copper alloy.
Answer:
x>2
Step-by-step explanation:
The arrow is facing the right hand side and the point on 2 isn't shaded so it's x greater than 2
Answer:
Below 70.5 because of the 68, 95, and 97.5 rule
Step-by-step explanation:
Decrease = (original number - new number) / original number .....x 100
decrease = (49 - 22) / 49.....* 100 =
(27 / 49) * 100 =
2700 / 49 = 55% decrease
$56.70 take away the tax first which brings you to $54 then 54x.10% is 5.40 so take 5.40 away from $54 you then have $48.60 then you can add the tax back in +2.70 = $51.30