
Here's the solution ~
As we know, we can calculate the circumference of a circle in terms of its diameter as :

where, c = circumference and d = diameter
And also, circumference of circle is terms of radius (r) is :

Now, let's move on to questions ~
<h3>First </h3>


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<h3>Second</h3><h3 /><h3 /><h3 /><h3>

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<h3>Third</h3>


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<h3>Fourth</h3>



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<h3>Fifth </h3>



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<h3>Sixth</h3>



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Answer:
the answer would be C
Step-by-step explanation:
What do you mean?
Expand your question
Let ‘s’ be the son’s age 12 years ago.
Let ‘f’ be the father’s current age.
4 years ago, the son was:
s-4
So, his father is currently:
3(s-4)
=
3s-12
Therefore:
f = 3s-12
In twelve years, the son will be:
s+12
And the father will be:
f+12
This can also be written as:
3s-12+12 as the fathers younger age would be f = 3s+12
=
3s
So, we know that s+12 is half the fathers current age, meaning the father is currently 2(s+12) which is equivalent to 2s+24. Also, we know that the father is currently 3 times the sons age 12 years ago, so 3s (proven by the calculations we made above). Therefore, 2s+24=3s which means 24=s. We can then substitute this, and we will receive 24+12 = 36
Son’s current age: 36
We then substitute the son’s age 12 years ago into 2s+24 to give us the father’s age.
2(24)+24 = 72
Father’s current age: 72