Question

A vaccine freezer with an extremely sensitive thermometer can measure fractions of a degree.

It sends a reading of the temperature once an hour. The table shows readings for 4 hours.
Which reading is the coldest?
8
a.m
Hour
Temperature -0.5
(°C)
10
a.m. a.m.
11
a.m.
2 -1.5 -2
0
1
The coldest reading was at a.m.
Order these numbers from least to greatest.

Answer 1

The coldest temperature reading was at 11 a.m. with a temperature of -2 °C. To order the temperatures from coldest to warmest, they would be: -2 °C, -1.5 °C, -0.5 °C.

Step-by-step explanation:

To determine which temperature reading is the coldest, we compare the given temperature values directly since they are all in degrees Celsius (°C). We need to remember that in the Celsius scale, a lower number indicates a colder temperature, and since we can have temperatures below zero (negative values), these are colder than temperatures above zero.

The readings given are -0.5 °C at 8 a.m., -1.5 °C at 10 a.m., and -2 °C at 11 a.m. When we compare these, -2 °C is the coldest temperature because it has the lowest value among all the readings. So, the coldest reading was at 11 a.m.

To order these numbers from least to greatest, we need to start with the smallest (or coldest) temperature and go up to the largest (or warmest):

• -2 °C (11 a.m.)
• -1.5 °C (10 a.m.)
• -0.5 °C (8 a.m.)