Samuel could round both of the individual numbers, to get s rounded answer. So, he could round 23 to 20, and 395 to 400, to get a product of 8000.
Or, he could multiply the numbers first, so 23*395 to get a product of 9085, which would then round to 9000, or depends on what place value it would want to be rounded to.
Answer:

Step-by-step explanation:
Please see the attached picture for the full solution.
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To make 90 tortillas, he needs to make 6 batches. 6*15=90
2 cups masa per batch ->. 2 * 6=12 cups Masa
1.5 water per batch -> 1.5. * 6= 9 cups water