Answer:
45% of the students at camped signed up for neither swimming or the zip line ⇒ 2nd answer
Step-by-step explanation:
To solve the problem let us use the following rules
n(swimming or zip line) = n(swimming) + n(zip line) - n(swimming and zip line)
n(neither) = n(total) - n(swimming or zip line)
∵ 70 signed up for swimming
∵ n(swimming) = 70
∵ There were 25 that signed up for zip line
∵ n(zip line) = 25
∵ 12 of those 25 students also signed up for swimming
∵ n(swimming and zip line) = 12
Use the 1st rule to find n(swimming or zip line)
∵ n(swimming or zip line) = 70 + 25 - 12
∴ n(swimming or zip line) = 83
∴ There were 83 students signed up in swimming or zip line
Use the 2nd rule to find n(neither)
∵ There were 150 students at summer camp
∴ n(total) = 150
∵ n(swimming or zip line) = 83
∴ n(neither) = 150 - 83
∴ n(neither) = 67
∴ There were 67 students signed up for neither swimming or the
zip line
To find the percent of the neither divide n(neither) by n(total), then multiply the quotient by 100%
∵ %(neither) = × 100%
∴ %(neither) = 44.6666667%
- Round it to the nearest whole number
∴ %(neither) = 45%
45% of the students at camped signed up for neither swimming or the zip line