Answer:
see explanation
Step-by-step explanation:
Given that y is inversely proportional to x then the equation relating them is
y = 
← k is the constant of proportionality
To find k use the condition that y = 7, x = 9
k = yx = 7 × 9 = 63, thus
y = 
← equation of proportion
When x = 21, then
y = 
= 3
To obtain a score of 85% on a test worth 135 points, one needs to get 115 points. By using proportions, we get the required value.
<h3>How to write proportions?</h3>
A proportion is defined as an equality between two ratios.
Consider two ratios a:b and c:d. Then, the proportion we can write,
a: b = c : d
Then, the simplification we have for this proportion is
a/b = c/d or ad = bc
<h3>Calculation:</h3>
It is given that, a certain test is worth 135 points.
One to get 85% on this test, he/she needs to get X number of points.
So, we can write the proportions as
X : 135 = 85 : 100
⇒ X/135 = 85/100
⇒ X = 85/100 × 135
∴ X = 114.75 ≅ 115 points
Learn more about proportions at the following link:
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The weight of each bag is 0.545 lb .
<h3>What is weight ?</h3>
Weight in maths is the value of the mass of an object on a measuring scale , It is measured in pound , ounce , kilogram etc.
It is given that
Total weight of green grapes = 5.65 lb
Total weight of red grapes = 3.07lb
Total weight = 5.65 +3.07 = 8.72 lb
Total number of bags = 16
the weight of each bag
= 8.72 / 16
= 0.545 lb
Therefore the weight of each bag is 0.545 lb .
The complete question is
Emilio bought 5.65lb of green grapes and 3.07lb of red grapes. He divided the grapes equally into 16 bags. If each bag of grapes has the same weight, how much does each bag weigh?
To know more about Weight
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