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# Subtracting 10s using place value

Sal subtracts 40 from 65 by thinking about place value.

## Want to join the conversation?

• Does place values work with decimals?
• There are decimal based place values.
• When Sal shows the 65 is equivalent to 6 tens + 5 ones, why doesn't he just do 65 = 60 + 5? He has already visually shown 6 tens and 5 ones with the drawing shown throughout the video length. Is the intention just to continue to think in place value?
• does place values work with decimals
• Good question! Yes, place values are used for decimals! Starting from the first digit to the right of the decimal point, and going further to the right, the place values are tenths, hundredths, thousandths, ten-thousandths, hundred-thousandths, millionths, ten-millionths, hundred-millionths, and so on forever. Observe that place values become smaller and smaller fractions as we go farther and farther to the right of the decimal point.

Have a blessed, wonderful day!
• hi what happens if you forget to cross out the base ten?
• You will end up with ten more than the actual answer. Say you do 22 - 5, you'll obtain 27 instead of 17.
• how many videos do you need to wach?
• You don't need to watch videos if you understand the concepts.
• How much is100_