Answer:
3400
Step-by-step explanation:
When you round to the tens place you look at the number in the ones place. If it is 4 or less then you keep the tens place the same. If it's 5 or more then you round the tens place up one. Then you make the ones digit a 0.
Since there is a 2 in the ones place in 172, you keep the tens digit the same (170).
Since there is an 8 in the ones place in 18, you round the tens digit up one (20).
Now you multiply.
170×20=3400
I hope that made sense.
