<p>Let the function f be defined by f(x) = x + 1 . If 2( f ) ( p) =20, what is the value of f(3p)?</p>
<p>answer was 28... i have never seen a problem like that before with both variables.</p>
<p>and ive seen this every time ive taken the PSAT and SAT prac test but i wnna kno how to do this properly</p>
<p>A measuring cup contaitns 1/5 of a cup of orange juice. It is then filled to the 1 cup mark with a mixture that contains equal amounts of orange, grapefruit, and pineapple juices. What fraction of the final mixture is orange juice?</p>
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<li>There aren't two variables in this problems...well there are but nothing to be confused about or scared of just handle it like this:</li>
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<p>2f(p)=20
f(p)=10=p+1
The above is true because f(p) is basically like plugging in p for x instead of a physical number.
p=9
f(3p)=f(3*9)=f(27)=27+1=28</p>
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<li>1/5 of a cup is filled with Orange Juice. Then it says the rest is filled up with a mixture of orange, grapefruit, and pineapple juices. So 4/5 of it is filled up with that mixture. It said that the mixture contains equal amounts of the juice so divide 4/5 by 3 to find the amount of Orange Juice in that mixture. Add that amount to the existing orange Juice (1/5) and that's how much orange juice u have (7/15). Since u have 1 cup total, divide (7/15) by 1 to get fraction of orange juice.</li>
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<p>Arbitrarily assume the volume of a cup 30 oz.
In the beginning: (1/5)30 = 6 oz of orange juice.
The remaining volume 30-6=24 oz is later equally divided between orange, grapefruit, and pineapple juices:
24:3=8 oz of each was added.
Now there is 6+8=14 oz of orange juice in the cup, which represents
14/30 = 7/15 of the final mixture.</p>