The mean temperature for the first 4 days in January was 7°C. The mean temperature for the first 5 days in January was 9°C. What was the temperature on the 5th day?

If the mean was 7 for the first 4 days that means the sum of temperatures of the first 4 days was 7 * 4 = 28. Similarly, the sum of temperatures of the first 5 days was 9 * 5 = 45 so that means that the temp. on the 5th day was 45 - 28 = 17°C.

answer: two angles are called supplementary if they add up to 180°. example: the two angles (140° and 40°) are supplementary because they add up to 180°.

step-by-step explanation:

the answer for the question that you are asking is 4