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a is directly proportional to b². a is also directly proportional to √c. When b = 3, the value of c is 567. What is the value of c when b = 5? If your answer is a decimal, then round it to 1 d.p. Search Watch video PRO K​

User Sarme
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The value of c when b = 5 is approximately 202.5.

Given that A is directly proportional to b² and a is also directly proportional to √c, we can write the following equations:

A = kb²

a = mc^(1/2)

where k and m are constants of proportionality.

When b = 3, the value of c is 162. We can substitute these values into the equations to find the values of k and m:

A = kb²

A = k(3)²

A = 9k

a = mc^(1/2)

a = m(162)^(1/2)

a = 9m

Now, we can use the fact that A and a are directly proportional to find the value of c when b = 5:

A = ka²

a = mc^(1/2)

Since A and a are directly proportional, we can write:

A/a = k/m = constant

Substituting the values we found earlier, we get:

A/a = (9k)/(9m) = k/m

Therefore, we can write:

ka²/mc^(1/2) = k/m

Simplifying this equation, we get:

a²/c^(1/2) = 1

Multiplying both sides by c^(1/2), we get:

a² = c

Substituting the values we found earlier, we get:

(9m)² = c

Simplifying this equation, we get:

81m² = c

Now, we can find the value of c when b = 5:

c = 81m² = 81(a/9)² = 81(25/9) = 202.5

Therefore, the value of c when b = 5 is approximately 202.5.

Complete question:

A is directly proportional to b².

a is also directly proportional to √c.

When b = 3, the value of c is 567.

What is the value of c when b = 5?

If your answer is a decimal, then round it to 1 d.p.

Any help please??

User Ppreetikaa
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