Dive Back into Division

10 min

Narrative

The purpose of this Warm-up is to elicit the idea that multiplication and division are related, which will be useful when students identify unknown dividends and divisors in a later activity. While students may notice and wonder many things about this equation, possible numbers to fill in the blanks are the important discussion points.

Launch

  • Groups of 2
  • Display the equation.
  • “What do you notice? What do you wonder?”
  • 1 minute: quiet think time
Teacher Instructions
  • “Discuss your thinking with your partner.”
  • 1 minute: partner discussion
  • Share and record responses.

Student Task

What do you notice? What do you wonder?

‾÷‾=136\underline{\hspace{1 cm}} \div \underline{\hspace{1 cm}} = 136

Sample Response

Students may notice:
  • There is a division sign.
  • There are two blanks.
  • The division expression has to be equal to 136.
  • 136 times a number in the second blank will be the number in the first blank. 
Students may wonder:
  • What numbers go in the blanks?
  • Can there be more than one answer?
  • How can I figure out what numbers go in the blanks?
  • Could the numbers be fractions or decimals?
Activity Synthesis (Teacher Notes)
  • “What numbers could go in the blanks? How do you know?” (I could put in 136 and 1 or 272 and 2. The first number has to be 136 times the second number, or the dividend needs to be 136 times the divisor.)
Standards
Addressing
  • 5.NBT.6·Find whole-number quotients of whole numbers with up to four-digit dividends and two-digit divisors, using strategies based on place value, the properties of operations, and/or the relationship between multiplication and division. Illustrate and explain the calculation by using equations, rectangular arrays, and/or area models.
  • 5.NBT.B.6·Find whole-number quotients of whole numbers with up to four-digit dividends and two-digit divisors, using strategies based on place value, the properties of operations, and/or the relationship between multiplication and division. Illustrate and explain the calculation by using equations, rectangular arrays, and/or area models.

15 min

20 min