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.
Answer:
The best deal is the middle one.
Step-by-step explanation:
35.95 with a 20% discount.
You can do this the straight forward way. Take 20% 35.95
20/100 * 35.95 = 7.19
Now subtract this from 35.95
35.95 - 7.19 = 28.76
15/100 * 29.75 = 4.46
29.75 - 4.46 = 25.28
25% * 38.49 = 9.62
38.49 - 9.62 = 28.86
Answer:
Obtuse.
Step-by-step explanation:
Answer:
x = 4
Step-by-step explanation:
To solve this equation, first you want to write the whole thing out.
32x - 1 = 243
Next you want to get the variable by itself, so you are going to use inverse operations. in the equation, it is 32x - 1, so you are going to add one to both sides, getting you this:
32x = 244
Now for the final step you are going to get x alone, so you are going to use inverse operations once more and divide 32 on both sides getting you your answer.
x = 4
Now if you want to check your work simply plug in x, and if it is equal, you got the correct answer!
I hope this helped and good luck with your math!
I'm really sorry if I'm wrong though, even though I already finished this unit a while ago I struggled on this one even though it is so easy compared to the equations I have now.
