standard_description: Add within 100, including adding a two-digit number and a one-digit number, and adding a two-digit number and a multiple of 10, using concrete models or drawings and strategies based on place value, properties of operations, and/or the relationship between addition and subtraction; relate the strategy to a written method and explain the reasoning used. Understand that in adding two-digit numbers, one adds tens and tens, ones and ones; and sometimes it is necessary to compose a ten.
problem_activity: Task
Decide which value is closest to the answer for each of the following questions. Explain your reasoning.
8 bottles each contained 1.2 liters of water. About how many liters of water were there all together?
| 0.1 | 1 | 10 | 100 |
|-----|---|----|-----|
A school bought 8.5 kilograms of apples. If apples cost $2.45 per kilogram, about how much did they pay (in dollars)?
| 0.2 | 2 | 20 | 200 |
|-----|---|----|-----|
A laptop contains about 0.0006 kilograms of gold. If a manufacturer plans to produce 10,100 of these laptops, about how many kilograms of gold are needed?
| 0.6 | 6 | 60 | 600 |
|-----|---|----|-----|


aligns: no