Let’s choose the first one, and do the proportions.
x/30 = 90/100
Cross multiply and you have
100x = (30)(90)
100x = 2700
x = 27
And the fourth one: multiply by the decimal equivalent of the percent.
90% = 90/100 = 0.9
0.9 x 30 = 27
You chose these because your “online tutor” finds them easiest to explain XD
