A bag contains purple marbles and green marbles, 31 in total. The number of purple marbles is 1 less than 3 times the number of green marbles. How many purple marbles are there?

6 green 25 purple

Step-by-step explanation:

option a is correct.

step-by-step explanation:

scale factor: it is used to find proportional measurements.

proportions means having the same ratio.

scale factor is the ratio of the model measurement to the actual measurement in a simplest form.

or we can say that the ratio of any two corresponding lengths in two similar geometric figures

if the scale factor is more than 1, then it is an enlargement,

if the scale factor less than 1, then it is a reduction.

given the two geometric figure:

by definition of proportions, we have

3

step-by-step explanation: