Answer:
50
Step-by-step explanation:
If the first statement its true (At most 0 of the statements are true), there are not true statements in the paper. So, the first statement its false.
Now, if the first statement its false, this mean there must be at least 1 true statement in the paper.
Now, if the second statement its true ( at most 1 of the statements are true) this implies that the third statement its true (if "at most 1" its true, then "as most 2" must be true).
If any statement (besides the first) its true, then all the statement that follows it must be true.
The first non false statement, then, must be the statement made by the person 51: "At most 50 statements are true"
And the 49 statements that follows are true as well.
Let 
be the random variable for the number of marks a given student receives on the exam.
10% of students obtain more than 75 marks, so
where 
follows a standard normal distribution. The critical value for an upper-tail probability of 10% is
where 
denotes the CDF of , and 
denotes the inverse CDF. We have
Similarly, because 20% of students obtain less than 40 marks, we have
so that
Then 
are such that
and we find
It takes 6 seconds for it to hit the ground.
0 = -5x²+20x+60
We can solve this by factoring. First factor out the GCF, -5:
0 = -5(x²-4x-12)
Now we want factors of -12 that sum to -4. -6(2) = -12 an -6+2 = -4:
0 = -5(x-6)(x+2)
Using the zero product property, we know that either x-6=0 or x+2=0; this gives us the answers x=6 or x=-2. Since we cannot have negative time, x=6.
Gosh, I've done this problem before. Let's start with 13. In this problem, we're basically just skip counting. For example, in the roses row, in the second bouquet, we know we have to add 4 more flowers, so we can document 8. Continue to skip count for both. For 15, we would have about 96 more movie posters remaining, making our ratio 96:x. So, 96:x = 120:100. Therefore, x would equal 80- as 96:80 equals 120:100. If she needs 80 and already had 100, she should sell 20 posters. Hope this helped.
We know that
If the scalar product of two vectors<span> is zero, both vectors are </span><span>orthogonal
</span><span>A. (-2,5)
</span>(-2,5)*(1,5)-------> -2*1+5*5=23-----------> <span>are not orthogonal
</span><span>B. (10,-2)
</span>(10,-2)*(1,5)-------> 10*1-2*5=0-----------> are orthogonal
<span>C. (-1,-5)
</span>(-1,-5)*(1,5)-------> -1*1-5*5=-26-----------> are not orthogonal
<span>D. (-5,1)
</span>(-5,1)*(1,5)-------> -5*1+1*5=0-----------> are orthogonal
the answer is
B. (10,-2) and D. (-5,1) are orthogonal to (1,5)
