You can find the circumference of the circle with the circumference equals 2pir.
circumference=2pi9
circumference=18pi
circumference=56.55 feet
you can then turn the feet into inches by multiplying by 12
(56.55 feet)x(12inches/foot)=678.58 inches
then divide 678.58 inches by 54 inches to find how many light strands are needed.
(678.58 inches)/(54 inches/strand)=12.57 strands
The probability density function (pdf) is;
f(x)=
for a ≤ x ≤ b.
while the mean is given as 
And the standard deviation given as 
The problem is 3+6x = 15 with x being the number of white numbers.
Isolate variable by subtracting 3 on both sides: 6x = 12.
Isolate variable by dividing 6 on both sides: x = 2
The number of white marbles is 2.
Answer:
The percent increase is 120%.