Answer:
14 quarters and 28 nickels
Step-by-step explanation:
System of Equations where x = number of quarters and y = number of nickels
(1) equation with value of each coin
0.25(x)+0.05(y) = 4.90
(2) total number of coins
x + y = 42
Solve system of equations using either substitution or elimination
(elimination multiplying equation 2 by -0.5)
.25(x) + 0.05(y) = 4.90
-0.05(x) - 0.05(y) = 42 * (-0.05)
(3) Resulting equation
.20(x) = 2.8
x = 14
plug x into equation 2
14 + y = 42
y = 28
There are 14 quarters and 28 nickels in Mary's collection.
Answer:
B
Step-by-step explanation:
<span>B.When x=-4, y=-9 and when x=2, y=3.
</span><span>3y-6x=-3
3(-9) - 6(-4)= -3
-27 +24 =-3
-3 = -3
</span>
<span>3y-6x=-3
3(3) -6 (2) = -3
9 - 12 = -3
-3 = -3
</span>
For perfect solution we need to have :- 8 colves in 500ml solution
500 ml has 8 cloves
1 ml has 8 / 500 cloves
100ml has 8 / 500 * 100 = 8/5 = 1.6 cloves
Raphael's mixture
900 ml has 12 cloves
1 ml has 12 / 900 cloves
100 ml has 12 / 900 * 100 = 12 / 9 = 1.33 cloves
so concentration of garlic in 100 ml solution of Raphael's solution is less than Emily's solution so it is not garlicky enough. ( option B)