Answer:
Step-by-step explanation: start at -39 degrees. You need to find how many degrees is between -39 and 10 degrees.
+39+10= 49 degrees risen
The answer is one solution. Hope this helps
The benchmarks are: 0, 0.25, 0.50, 0.75 and 1.
2. 81 → 2.75
+
3.73 → 3.75
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2.75 + 3.75 = 6.50
The two numbers are very near 7200 and 300. The sum of those is a good estimate of your sum:
... 7200 + 300 = 7500
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If you're taught methods of addition that include "make a ten" or "make a hundred", you know you can "borrow" a 1 from 7203 (making it 7202) and loan that 1 to 299 to make it 300. Now, you know your sum is exactly 7202+300 = 7502, with no estimation necessary.