50 percent of the group randomly selected that are male and female
Answer:
1/(c - d)
Step-by-step explanation:
Multiply numerator and denominator by cd, then factor the denominator and cancel the common factor. (The result is restricted to c+d ≠ 0.)

Let
Y=the food is yummy
O=overeat
E=exercise
Note:
∪ = or
-> if ... then
(Y∪O)->E
Step-by-step explanation:
Pythagoras' theorem for the smallest one :


= 52
Pythagoras' theorem for the middle one :
=
+ 
Pythagoras' theorem for the biggest one :


Using the formula before (for
) it becomes :



16 + 8a = 52 + 36
16+8a = 88
8a = 88-16
8a = 72
a = 9
Verifying :



= 117
The biggest one :



True
Colfax:
Add the ratio numbers together:
5 + 4 = 9
Divide total students by that:
270 / 9 = 30
Multiply each ratio by 30:
Boys = 30 *5 = 150
Girls = 30 * 4 = 120
Do the same for Winthrop:
4 +5 = 9
180 /9 = 20
Boys = 20 * 4 = 80
Girls = 20 * 5 = 100
Total students = 270 + 180 = 450
Total Girls = 120 + 100 = 220
Fraction that are girls = 220 / 450 which reduces to 22/45