It was found that 72% of students took mathematics and 53% took
chemistry. 77% of students took mathematics or chemistry. how many percent took math only? How do you solve this? The answer is 24%.
2006-08-11 14:14:10 · 3 answers · asked by Anonymous in Education & Reference ➔ Primary & Secondary Education
First, you can ignore the percents. Everything is in percent, so the math will come out right.
Let's define a few variables:
m = took math only
c = took chemistry only
x = took math and chemistry
So, m + x = 72. c + x = 53. m + c + x = 77.
Solving for m from there is easy. You don't even need the first equation.
m + c + x = 77
m + 53 + 77
m = 24.
2006-08-11 14:32:00 · answer #1 · answered by Muralasa 3 · 0⤊ 0⤋
Since you have percentages, assume that there are 100 students. Make the percentages real numbers:
72: mathematics.
53: chemistry.
77: mathematics or chemistry.
If 77 took one or the other, than 23 took neither mathematics nor chemistry using 100 as the total.
Subtract all of those taking chemistry (53) from the total of those taking one or the other (77) and you'll get an answer of 24 that took math only. Make that a percentage again = 24%.
2006-08-11 14:30:13 · answer #2 · answered by Anonymous · 1⤊ 0⤋
77% - 53% = 24%
2006-08-11 20:04:52 · answer #3 · answered by Wide Ruled Paper 3 · 1⤊ 0⤋