Answer:
B. unit of account
Step-by-step explanation:
Accounts are kept in terms of units of account. Money serves as the unit of account when accounts are kept in terms of money.
15% of 20 gal = 0.15 * 20 gal = 3 gal, so the solution contains 3 gal of salt.
If we add <em>x</em> gal of water to the solution, we end up with (20 + <em>x</em>) gal of solution. We want the new mixture to have a concentration of 10%, or
10% of (20 + <em>x</em>) gal = 0.1 * (20 + <em>x</em>) gal = 2 + 0.1<em>x</em> gal
of salt.
The amount of salt in the tank hasn't changed. Solve for <em>x </em>:
2 + 0.1<em>x</em> = 3
0.1<em>x</em> = 1
<em>x</em> = 10 gal
<h2>
Answer:</h2>
<h2>
Explanation:</h2>
<em>The height of the rider from the ground after the Ferris wheel</em> equals <em>the starting point is 15 feet off the ground </em><em>plus </em><em>the radius of the Ferris wheel </em><em>plus </em><em>the opposite side of the triangle ΔABC </em>(See figure below).<em> </em>Hence our goal is to find this side. We have the angle 
, therefore the angle ∠BAC = 165° - 90° = 75°. So this side can be found using trigonometry:
Finally, the height is:
X=price of one jumbo popcorn
y=price of one chocolate chip cookies
$5.00=$5.00(100 cts / $)=500 cts
$6.00=$6.00(100 cts / $)=600 cts
We suggest this system of equations:
x+2y=500
x+4y=600
we solve this system of equations by reduction method.
-(x+2y=500)
x+4y=600
----------------------
2y=100 ⇒ y=100/2=50
x+2y=500
x+2(50)=500
x+100=500
x=500-100
x=400
solution: one chocolate chip cookie cost 50 cts.
Answer:
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Step-by-step explanation:
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