D, because for each element of the set of X, there is only one corresponding element of the set of Y.
Well the angles should all equal 360. Since you know 90 and 160 then 360-90-160=110. Angle 2 is 90* so 110-90=20 so angle 4 is 20. Angle 2+ angle 4: 90+20=110 or C :)
Answer: Well if you were going to think of a circle you can divide it into 4 equal sizes in one of the is equal to two pentagons and a half. If you add all is equal to a loop full of pentagons [which makes 10 pentagons]. Because the ring is made out of regular pentagons, we can work out that each of the interior angles of each pentagon is 108* degrees. By extending the lines that two pentagons share, assuming they will all meet in the middle, it will create a triangle. As we know each angle of a [regular] pentagon is 108* degrees, we know the two base angles of the triangle would equal to 72** which leaves the top angle to be 36 degrees. As [the sum of] angles at a point is 360 degrees, and 36 is divisible by 360, it will make a complete ring. Also, as 360 ÷ 36 = 10, we know that the ring will be made out of 10 pentagons. as formula to calculate the the size of a interior angle of a polygon is (n×180−360)÷n (for n being the number of sides that the polygon has). because the triangle is made by extending the lines, and angles on a line is 180 degrees, 180−108 (an interior angle of a pentagon) =72.
Largest integer: 57
x + x + 1 + x + 2 = 168
3x + 3 = 168
-3 -3
3x = 165
/3 /3
x = 55
x = smallest integer = 55
x + 1 = middle integer = 55 + 1 = 56
x + 2 = largest integer = 55 + 2 = 57
500 people took the survey.
12 out of 15 people is 80% of the population. 12/15 = 0.80
Thus, 80% of the population prefers eating in the restaurant.
If 400 represents the people who prefers eating in the restaurant; then, 400 is the 80% of the population. To get the total population or 100%, we must divide 400 by 0.80 or 80%
400 / 0.80 = 500 people.
Out of the 500 people, 400 selected eating in the restaurant while the remaining 20% of the population or 100 people selected cooking at home.
