If the radius of the circle is doubled, by what number is the circumference multiplied?

The number by which the circumference is multiplied is:

                               2

We know that the circumference of the circle in terms of the radius r is given by:

Now, if the radius is doubled.

i.e.

Hence, the circumference of the new circle is given by:

i.e.

The constant by which the circumference is multiplied is: 2

mx+89b(-98)nb

step-by-step explanation:

b) 1/3 * 1/5

step-by-step explanation:

each smallest part is 1/15 since the written one is 1/5 and it's divided by 3 equal parts. (1/5 )/3 = 1/15 = 1/3 * 1/5