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• ﻿﻿﻿﻿Isabella, I'm confused about decimal multiplication. Do you understand it?
• ﻿﻿﻿﻿﻿﻿﻿﻿﻿﻿﻿No, I still don't know where the decimal goes. I hope Ms. Resnick goes over it again today.
• ﻿﻿﻿Yesterday we learned about decimal multiplication.
• ﻿Good morning. Many students find decimal rules confusing.
• ﻿﻿﻿﻿I want to make sure you understand how to do it correctly.
• ﻿﻿When we add or subtract decimals, we line them up. Do we also do this when we multiply?
• ﻿﻿Juan?
• ﻿﻿﻿No, we have to line up the numbers.
• ﻿﻿Finally, in the product, we count from right to left the same number of places and put the decimal point there.
• ﻿﻿Then we count the digits to the right of the decimals in both factors.
• ﻿That's right, Juan. We line up the numbers and multiply like normal. ﻿
• ﻿﻿Okay, let's try a practice problem. What is 4.21 x 3.8?
• ﻿﻿Awesome job! Can someone explain why Laila put the decimal between the 5 and the 9?
• ﻿It's 15.998!
• ﻿﻿Isabella?
• ﻿You're right! ﻿Great explanation!
• ﻿﻿I get it now! There are 3 digits to the right of the factors, so we have to move the decimal point 3 places to the left in the product.