Answer:
28
Step-by-step explanation:
KARLEE HAS 4 PENCIL PACKS.
<h3>1 PENCIL = 1/7 of pack.</h3>
∴ 1 pack has 1/7 multiplied by X.
X/7 = 1, so X is 7.
AND THEREFORE 4 PACKS CONTAIN 7*4 = 28
Answer:
$4080
Step-by-step explanation:
We have the amount she will pay back, but first, we need to find the Interest accrued.
Simple Interest is given as:
where P = principal
R = rate
T = time taken (in years)
Therefore, the interest on $3,000 at 9% simple interest for 4 years is:
I = $1080
Therefore, the amount she will pay back is:
$3000 + $1080 = $4080
Answer:
212 children, and 265 adults
Step-by-step explanation:
To find the number of children and adults, we can set up a systems of equations.
x= number of children
y= number of adults
Equation 1: Price
1.50x+2.25y=914.25
Equation 2: Total number of people
x+y=477
Now, let's solve the equation using substitution.
Rearrange the second equation to solve for one variable.
x+y=477
x=477-y
Now plug x equals into the first equation, and solve for y.
1.50x+2.25y=914.25
1.50(477-y)+2.25y=914.25
715.5-1.50y+2.25y=914.25
715.5+0.75y=914.25
0.75y=198.75
y=265
We just solved for the number of adults. Now let's plug y equals into the second equation to find the number of children.
x+y=477
x+265=477
x=212
Ok, I'm going to start off saying there is probably an easier way of doing this that's right in front of my face, but I can't see it so I'm going to use Heron's formula, which is A=√[s(s-a)(s-b)(s-c)] where A is the area, s is the semiperimeter (half of the perimeter), and a, b, and c are the side lengths.
Substitute the known values into the formula:
x√10=√{[(x+x+1+2x-1)/2][({x+x+1+2x-1}/2)-x][({x+x+1+2x-1}/2)-(x+1)][({x+x+1+2x-1}/2)-(2x-1)]}
Simplify:
<span>x√10=√{[4x/2][(4x/2)-x][(4x/2)-(x+1)][(4x/2)-(2x-1)]}</span>
<span>x√10=√[2x(2x-x)(2x-x-1)(2x-2x+1)]</span>
<span>x√10=√[2x(x)(x-1)(1)]</span>
<span>x√10=√[2x²(x-1)]</span>
<span>x√10=√(2x³-2x²)</span>
<span>10x²=2x³-2x²</span>
<span>2x³-12x²=0</span>
<span>2x²(x-6)=0</span>
<span>2x²=0 or x-6=0</span>
<span>x=0 or x=6</span>
<span>Therefore, x=6 (you can't have a length of 0).</span>
