Calories consumed by members of a track team the day before a race are normally distributed, with a mean of 1,800 calories and a standard deviation of 100 calories. If a normal curve is sketched using these data, what is the range for 3 standard deviations to the right and to the left of the mean? 0–3,600

1,700–1,900

1,600–2,000

1,500–2,100

The answer is 1,500–2,100

How to find this:

The mean is 1800
The standard deviation is 100

(Subtract 100 from the mean 3 times)
1800 - 100 = 1700
1700 - 100 = 1600
1600 - 100 = 1500

(Add 100 to the mean 3 times)
1800 + 100 = 1900
1900 + 100 = 2000
2000 + 100 = 2100

(The answers are your range)
1500 - 2100

I just took the test, hope this helps!