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R is inversely proportional to A.
R = 12 when A = 1.5
a) Work out the value of Rwhen A= 5.
b) Work out the value of A when R = 9

Respuesta :

Here are the answer: a) R = 3.6 and b) A = 2

Step-by-step explanation:

Given,

R is inversely proportional to A.

R ∝ [tex]\frac{1}{A}[/tex]

so, R = [tex]\frac{k}{A}[/tex]  -------eq 1 where k is any constant

To find the values of a) R when A = 5 and

b) Value of A when R = 9

Now,

Putting R = 12 and A = 1.5 in eq 1 we get,

12 = [tex]\frac{k}{1.5}[/tex]

or, k = 12×1.5 = 18

From eq 1 we get,

R = [tex]\frac{18}{A}[/tex] --------- eq 2

Now,

a) Putting A= 5 in eq 2 we get,

R = [tex]\frac{18}{5}[/tex] = 3.6

b)  Putting R = 9 in eq 2 we get

R = [tex]\frac{18}{A}[/tex]

or, A = [tex]\frac{18}{9}[/tex] = 2

Answer:

a.3.6

b. 2

Step-by-step explanation:

R is inversely proportional to A

Which means R=k/A

Cross multiply

k=RA

Since R=12

A=1.5

So k=12×1.5

=18

a. We are to determine the value for R

So R=k/A

=18/5

=3.6

b.we are to determine the value for A

So R=k/A

A=k/R

=18/9

=2