He needs 160 5-star reviews in a role. We can write a function to solve this problem. His current total stars is 4.4*160=704. Suppose he needs x more 5-star reviews, then his total stars will be 704+5x. 160+x is the new number of reviews, and the new average will be 4.7, so 4.7*(160+x)=704+5x. The solution is 160. Besides, if you want to get the answer really fast, you can see that 4.7 is right in the middle of 4.4 and 5, so you can immediately guess that the number of new 5-star reviews should be equal to the number of current reviews.
Answer:
x = 12
Step-by-step explanation:
First, eliminate the fractional coefficient 1/2, by multiplying all three terms by 2:
-24 + x = -12
Adding 24 to both sides isolates x: x = -12 + 24, or x = 12
The domain is a discrete set. So we will have a discrete range.
The range is a set containing:
f(-2)=-11
f(-1)=-9
f(0) = -7
f(1) = -5
f(2) = -3
Range = {-11,-9,-7,-5,-3}
The amount of liters is 200,if the orange juice is x than grape juice. 200-x
45x+35(200-x)=200*40
45x+7000-35x=8000
10x=1000
x=100