Answer:
512
Step-by-step explanation:
Suppose we ask how many subsets of {1,2,3,4,5} add up to a number ≥8. The crucial idea is that we partition the set into two parts; these two parts are called complements of each other. Obviously, the sum of the two parts must add up to 15. Exactly one of those parts is therefore ≥8. There must be at least one such part, because of the pigeonhole principle (specifically, two 7's are sufficient only to add up to 14). And if one part has sum ≥8, the other part—its complement—must have sum ≤15−8=7
.
For instance, if I divide the set into parts {1,2,4}
and {3,5}, the first part adds up to 7, and its complement adds up to 8
.
Once one makes that observation, the rest of the proof is straightforward. There are 25=32
different subsets of this set (including itself and the empty set). For each one, either its sum, or its complement's sum (but not both), must be ≥8. Since exactly half of the subsets have sum ≥8, the number of such subsets is 32/2, or 16.
12x/15-10x/15
=2x/15 is your answer
Answer:
Zero
Step-by-step explanation:
3x - 7 = 3x - 9 + 2
3x - 7 = 3x - 7
Add 7 on both sides
3x = 3x
Subtract 3x you get 0.
Hope this helps.
Answer:you measured the amount of rainfall incorrectly, your data about the climate would be inaccurate. Accuracy means being very precise and getting the information right. When something is inaccurate, it is the opposite of exact.
Step-by-step explanation:yw
Answer:
You can solve it by saying half times base times perpendicular high
