Hi! here are the steps to doing this:
1. Ok so we have 2.16 and 3, how can we use base tens? What you want to do is remove the decimal from 2.16 and add a digit to the end of it. Now add three digits at the end of 3. You would get 2,160 and 3,000.
2. Now we use the base ten blocks. Ok, so now we're gonna do some division. 2,160 divided by 10 is 216. You will have 216 base ten blocks for 2. Now for 3000. Three thousand divided by 10 is 300. You will have 300 base ten blocks for 3.
3. Finally we're here. What you want to do now is compare the amount of base ten blocks. For 2 you have 216 base ten blocks. For 3 you have 300. So, 216 is less than 300.
Ok, so the answer is less than. Hope I helped!