From the given information, a exists jointly proportional to b and c.
then 
Therefore, the value of a exists 2.
<h3>
What is the value of a?</h3>
Given, a exists jointly proportional to b and c.

Taking K as the constant of proportionality.
a = K b c
For b = 8 and c = 9, the value of a = 4
4 = K(8)(9)
4 = 72 K
Dividing the equation by 72, we get

Using the value of K in the equation:

Substitute the values of b = 2 and c = 18, in the above equation

a = 2
Therefore, the value of a exists 2.
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Answer:
9
Step-by-step explanation:
21^2-19^2=80
sqaure root of 80 to the nearest 10th is
Answer:
The model is made in a<u> 1:40 ratio
</u>
Step-by-step explanation:
How many times is 4 multiplied to be equal to 160?
4(x) = 160
X = 160 / 4
<u>X = 40</u>
The proportion, rate, and ratio are almost the same.
They represent the correspondence between the parts and the whole since they all express a binary relationship between the quantities, that is, objects, people, tablespoons.
If the ratio is 1: 2 it could be read that for every 1 there are 2.
For example 1: 2 cups; For every cup of something there are 2 cups of something else.
In this case, 1:40; For every inch of the model, there are 40 feet in the playground.
5.1 and the “1” is repeating