Answer: nickels = 14, dimes = 42, quarters = 18
<u>Step-by-step explanation:</u>
Let n represent nickels <em>which has a value of $0.05 </em>
Let d represent dimes <em>which has a value of $0.10</em>
Let q represent quarters <em>which has a value of $0.25</em>
It is given that:
n = n
d = 3n
q = n + 4
and their total value is $9.40 ⇒ n + d + q = $9.40
Use substitution to find the quantity of nickels:
.05(n) + .10(3n) + .25(n + 4) = 9.40
5n + 10(3n) + 25(n+4) = 940 <em>multiplied by 100 </em>
5n + 30n + 25n + 100 = 940 <em>distributed</em>
60n + 100 = 940 <em>added like terms</em>
60n = 840 <em>subtracted 100</em>
n = 14 <em>divided by 60</em>
n = 14
d = 3n
= 3(14)
= 42
q = n + 4
= (14) + 4
= 18
X+2y
Plug in the variables
4+2(7)
4+14
x+2y=18
Let x = the width
then
2x = the length
:
The box dimensions: 2x by x by 4
Given the surface area:
2(2x*x) + 2(2x*4) + 2(x*4) = 220
:
4x^2 + 16x + 8x = 220
A quadratic equation:
4x^2 + 24x - 220 = 0
simplify, divide by 4
x^2 + 6x - 55 = 0
Factor
(x+11)(x-5) = 0
The positive solution is what we want here:
x = 5 ft is the width
then
2(5) = 10 ft is the length
:
Find the volume
10 * 5 * 4 = 200 cu/ft is the volume
Answer:
0.25
Step-by-step explanation:
Prime outcomes on a die: 2,3,5
P(prime) = 3/6 = 1/2
Even outcom: 2,4,6
P(even) = 3/6 = 1/2
P(prime & even)
= P(prime) × P(even)
= ½ × ½
= ¼ or 0.25