Question

problems 1–5: one moment in december, it was -8°c in harbin, china, and -2°c in beijing, china. use the number line if it helps with your thinking.

1. which city was colder?
2. at the same moment, it was 7 degrees warmer in shanghai than it was in beijing. what was the temperature in shanghai?
3. how many degrees warmer was it in shanghai than in harbin?
4. later in the day, beijing got 5 degrees colder. what was beijing’s new temperature?
5. later in the day, harbin’s temperature was 1°c. by how much did harbin’s temperature change? explain your thinking.

Explanation:

Problem 1

Step1: Recall temperature comparison

Colder means lower temperature. Harbin: \(-8^\circ C\), Beijing: \(-2^\circ C\). On number line, \(-8 < -2\), so Harbin is colder.

Step1: Use Beijing's temperature

Beijing's temp: \(-2^\circ C\). Shanghai is \(7^\circ C\) warmer. So add \(7\) to \(-2\).

Step2: Calculate \(-2 + 7\)

\(-2 + 7 = 5\). So Shanghai's temp is \(5^\circ C\).

Step1: Identify temperatures

Harbin: \(-8^\circ C\), Shanghai: \(5^\circ C\) (from Problem 2).

Step2: Find temperature difference

Subtract Harbin's temp from Shanghai's: \(5 - (-8) = 5 + 8 = 13\). So Shanghai is \(13^\circ C\) warmer.

Answer:

Harbin

Problem 2