Jin solves the equation Negative 225 divided by (negative 15).

Which solution would help Jin determine the reasonableness of his answer?
dividing –25 by –10
multiplying –25 by –10
dividing –200 by –10
multiplying –200 by –10

1 answer

To determine the reasonableness of Jin's answer when solving the equation \(-225 \div (-15)\), one effective way is to compare it with a similar, simpler calculation that has the same divisor.

Looking at Jin's calculation, we notice:

Original Problem: \[ -225 \div (-15) = 15 \]

To check the reasonableness, let’s consider the options provided:

  1. Dividing -25 by -10 produces: \[ -25 \div -10 = 2.5 \] This does not relate well to the original problem.

  2. Multiplying -25 by -10 produces: \[ -25 \times -10 = 250 \] This is not directly comparable either.

  3. Dividing -200 by -10 produces: \[ -200 \div -10 = 20 \] This is a reasonable calculation since it also involves negative numbers and results in a positive number.

  4. Multiplying -200 by -10 produces: \[ -200 \times -10 = 2000 \] This is again not directly comparable.

Among the options, dividing -200 by -10 is the best choice to help Jin evaluate the reasonableness of his answer since it involves division and uses similar negative quantities, yielding a positive result.

So, the answer is: Dividing -200 by -10.