At 9 am the thermometer read 3 ° C. The air temperature rose by 2 ° C every hour. what is the air temperature at 12 noon?

If at 9 o’clock the temperature was 3 ° C and every hour it rose by 2 ° C, then at 10 o’clock the temperature was: 3 ° C + 2 ° C = 5 ° C, at 11 o’clock: 5 ° C + 2 ° C = 7 ° C, at 12 o’clock: 7 ° C + 2 ° C = 9 ° C.

Another solution.

Let’s find the difference in time: 12 hours – 9 hours = 3 hours. Since every hour the temperature rose by 2 ° C, during this time it rose: 3 hours * 2 ° C = 6 ° C. The initial temperature was 3 ° C, increased by 6 ° C, which means that by 12 o’clock the temperature was: 3 ° C + 6 ° C = 9 ° C.

Answer: by 12 noon the air temperature was 9 ° C.