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a class of 24 students went on a picnic. they had a choice between havi…

Question

a class of 24 students went on a picnic. they had a choice between having a turkey sandwich or a vegetarian sandwich. eighteen students selected turkey, and the rest selected vegetarian. write a ratio to compare the number of turkey sandwiches to the number of vegetarian sandwiches. 4:3 4:1 1:3 3:1 question 8 (5 points) fatima is on the track team. one day at practice, it took her 19 minutes to run 2 miles. select the expression that gives this as a unit rate. \\(\frac{19 \text{ minutes}}{2 \text{ miles}}\\) \\(9\frac{1}{2}\\) miles per minute. \\(\frac{1 \text{ mile}}{9\frac{1}{2} \text{ minutes}}\\)

Explanation:

Response
First Question (Ratio of Turkey to Vegetarian Sandwiches)

Step1: Find number of vegetarian sandwiches

Total students = 24, Turkey = 18. So Vegetarian = \( 24 - 18 = 6 \).

Step2: Find the ratio

Ratio of Turkey to Vegetarian = \( 18:6 \). Simplify by dividing both by 6: \( \frac{18}{6}:\frac{6}{6} = 3:1 \).

Step1: Recall unit rate definition

Unit rate for time per mile (or mile per minute) – here, to find time per 1 mile, divide total time by total miles.

Step2: Calculate unit rate

Total time = 19 minutes, total miles = 2. Unit rate (time per mile) = \( \frac{19}{2} = 9\frac{1}{2} \) minutes per mile? Wait, no – wait, the options: Let's re - evaluate. Wait, unit rate for miles per minute: miles divided by time. But the options: The first option is \( \frac{19\ minutes}{2\ miles} \), which is time per mile (unit rate for time per mile). Wait, the third option: \( \frac{1\ mile}{9\frac{1}{2}\ minutes} \) is equivalent to \( \frac{2\ miles}{19\ minutes} \) (since 1 mile in \( 9\frac{1}{2}=\frac{19}{2} \) minutes, so 2 miles in 19 minutes). Wait, the correct unit rate for time per mile is \( \frac{19\ minutes}{2\ miles} \), but let's check the options again. Wait, the third option: \( 9\frac{1}{2}=\frac{19}{2} \), so \( \frac{1\ mile}{\frac{19}{2}\ minutes}=\frac{2\ miles}{19\ minutes} \), which is the rate of miles per minute? No, wait, no. Wait, Fatima ran 2 miles in 19 minutes. So miles per minute is \( \frac{2}{19} \) miles per minute, and minutes per mile is \( \frac{19}{2}=9\frac{1}{2} \) minutes per mile. But the options: The first option is \( \frac{19\ minutes}{2\ miles} \) (which is minutes per mile, unit rate for time per mile), the third option is \( \frac{1\ mile}{9\frac{1}{2}\ minutes} \) (which is miles per minute? No, \( \frac{1\ mile}{9\frac{1}{2}\ minutes}=\frac{2\ miles}{19\ minutes} \), which is the same as her rate). Wait, the correct unit rate (time per mile) is \( \frac{19}{2}=9\frac{1}{2} \) minutes per mile, but the options: Wait, the first option is \( \frac{19\ minutes}{2\ miles} \), which is the unit rate for time per mile (since it's time divided by distance, giving time per 1 unit of distance). Wait, maybe I misread. Let's check the options again:

Option 1: \( \frac{19\ minutes}{2\ miles} \) – this is time per mile (unit rate for time per mile).

Option 2: \( 9\frac{1}{2}\ miles\ per\ minute \) – that would mean she runs \( 9\frac{1}{2} \) miles in 1 minute, which is wrong (she ran 2 miles in 19 minutes, so way slower).

Option 3: \( \frac{1\ mile}{9\frac{1}{2}\ minutes} \) – since \( 9\frac{1}{2}=\frac{19}{2} \), this is equivalent to \( \frac{2\ miles}{19\ minutes} \) (multiply numerator and denominator by 2), which is her actual rate. Wait, but unit rate for miles per minute is \( \frac{2}{19} \) miles per minute, and \( \frac{1\ mile}{9\frac{1}{2}\ minutes} \) is the same as \( \frac{2}{19} \) miles per minute (since \( \frac{1}{\frac{19}{2}}=\frac{2}{19} \)). But the first option is \( \frac{19\ minutes}{2\ miles} \), which is time per mile (9.5 minutes per mile). Wait, the question says "the expression that gives this as a unit rate". Unit rate can be time per unit distance or distance per unit time. Let's see:

If we want time per 1 mile: \( \frac{19\ minutes}{2\ miles} \) simplifies to \( \frac{9.5\ minutes}{1\ mile} \), which is the unit rate for time per mile.

If we want miles per 1 minute: \( \frac{2\ miles}{19\ minutes}=\frac{1\ mile}{9.5\ minutes} \), which is the third option.

Wait, the question says "the expression that gives this as a unit rate". Let's check the options again. The first option is \( \frac{19\ minutes}{2\ miles} \) (unit rate of minutes per mile), the third option is \( \frac{1\ mile}{9\frac{1}{2}\ minutes} \) (unit rate of miles per minute, since it's 1 mile in \( 9\frac{1}{2} \) minutes). Wait, but let's calculate:

To find miles per minute: \( \frac{2\ miles}{19\ minu…

Answer:

D. 3 : 1

Second Question (Unit Rate for Fatima's Running)