To compare the numbers, we'd better convert the fractions into decimals.
–6 3/4 = –6.75
27/5 = 5.4
–5 5/8 = –5.625
Now that the numbers are –6.6, 5.8, –6.75, 5.4 and –5.625.
a) A negative number is always less than a positive number. In addition, a negative with a larger magnitude would be less. Like –4 < –3. So the order from least to greatest is –6.75 < –6.6 < –5.625 < 5.4 < 5.8. In other words, –6 3/4 < –6.6 < –5 5/8 < 27/5 < 5.8.
b) A negative change means that the gas price decreased. The gas station that decreased the gas price the most is the Star gas since the –6 3/4 is the least number in the list.
c) The changes in prices can be compared in relation to each other based on their magnitude, which is the value without the sign. For example, the magnitude of –4 is 4. The magnitudes of the changes in prices are 6.6, 5.8, 6.75, 5.4 and 5.625. So the least change is 5.4, that is, 27/5. So the Corner Store changed the price the least.