in a colledge there are 20 students enrolled in commerce only 90 students enrolled in mathematics only, 30 students enrolled in both math and commerce and 60 enrolled for others find the number of students enrolled either in mathematics or economics

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

it is 570

step-by-step explanation: