7th Grade
5.2 Multiplying and Dividing Rational Numbers
Multiplying:
Fractions:
1) Change mixed numbers to improper fractions.
2) Simplify if you can (if you are not positive on how to do it then skip this step.)
3) Multiply straight across.
4) Check your answer. Make sure the sign is correct and that your answer is simplified.
Decimals:
1) Line up the numbers (not the decimals).)
2) Multiply
3) Count how many numbers are after both decimals.
4) Check your answer to make sure the sign and decimal are correct.
Dividing:
Fractions:
1) Change mixed numbers to improper fractions.
2) Flip only the second fraction and multiply the two numbers (its call multiplying the
reciprocal).
3) Now follow the multiplying fractions steps above.
Decimals:
1) Write as a long division problem.
2) Move the decimal to the end of the divisor.
3) Now move the decimal the same amount on the divided that you did on the divisor.
4) Long divide.
5) The decimal will go straight up. So MAKE SURE YOU NUMBERS ARE LINED UP!
6) Check your answer to make sure you have your sign correct.
Answer = −1.3