4. a student's work to solve 2 6/7 divided by 2/7 is shown below. which of the following statements do you agree with?
2 6/7 divided by 2/7 =
19/7 divided by 2/7=
7/19 times 2/7=
7/19 times 2/7=2/19 cross out the 7 in the first one put a one and cross out the second one and put a one
a. myriah the only mistake is in changing the mixed number to an improper fraction
b thomas. there's a mistake with the multiplication inverse of 2/7
c gabriel the problem looks fine to me
d siri there is a mistake with changing the mixed number to an improper fraction as well as changing the division problem to multiplication
I think it's D.
so do I.
To solve 2 6/7 divided by 2/7, let's break down the steps shown in the student's work:
Step 1: 2 6/7 divided by 2/7
To divide fractions, we multiply the dividend (2 6/7) by the reciprocal of the divisor (2/7).
So, the first step is correct.
Step 2: 19/7 divided by 2/7
Converting the mixed number 2 6/7 to an improper fraction, we get 20/7 (since 2 multiplied by 7 is 14 and adding 6 gives us 20), not 19/7.
So, there's a mistake in changing the mixed number to an improper fraction.
Step 3: 7/19 times 2/7
This step correctly multiplies the fractions.
Step 4: 7/19 times 2/7 = 2/19
This step correctly simplifies the multiplication.
However, in the explanation given in the student's work, there are additional mistakes mentioned. The student suggests crossing out the 7 in the first fraction and replacing it with 1. In doing so, the student mixed up the numerator and denominator, which is incorrect.
Therefore, the correct statement is:
d. Siri, there is a mistake with changing the mixed number to an improper fraction as well as changing the division problem to multiplication.