Two similar circles are shown. The circumference of the larger circle, with radius OB, is 3 times the circumference of the smaller circle, with radius OA. Two circles are shown. The smaller circle has radius O A and the larger circle has radius O B. Radius OB measures x units. Which expression represents the circumference of the smaller circle with radius OA? (StartFraction pi Over 3 EndFraction)x units (StartFraction 2 pi Over 3 EndFraction)x units 2πx units 6πx units

its 2pi/3

Step-by-step explanation:

because the full radian measure of a circle is 2pi radians, the smaller circle is a third of the size of the larger one. Multiply straight across for (2pi/1)(1/3)  

the arc length is found by finding the circumference of the full circle (2xpixradius) and then dividing by 4 to find just one quarter of the circle (90 degrees).

x is the total time in minutes for the free response

you are given number of questions as 15 - m and time per item as 8 minutes

to find x multiply the two givens together:

x = 8 * (15-m) = 8(15-m)