To find X, the answer would be 2
Answer:
66
Step-by-step explanation:
If there are <em>n</em> students, then the number of pairs is
.
With 12 students,
pairs can be formed.
The reason the formula works is this: Each of the 12 students can be paired with 11 other students (no student is paired with him/her self). But counting 12 x 11 = 132 counts each pair <u>twice</u>. Example: student A can be paired with student B,..., student B can be paired with student A. The pair was counted two times.
See the attached image that shows pairings of 5 students. There are
5(5 - 1)/2 = 5(4)/2 = 10 pairs.
Answer:
21
Step-by-step explanation:
since its a rectangle there are two lengths of six. If you add them together you get 12. subtract the total perimeter of 54 by the 12 and get 42. Since there is 2 sides left divide by 2. You should get 21 for the width of the rectangle
Answer:
Option B, would be the correct option as she sets it in the attic window. I hope this helps you! :)