<h3>
Answer: 7/19</h3>
Explanation:
There are 7 blue marbles out of 4+7+8 = 11+8 = 19 total
The probability of selecting blue is therefore 7/19
We cannot reduce 7/19 any further because 7 and 19 have no common factors other than 1.
The cube root of 2 is irrational. The proof that the square root of 2 is irrational may be used, with only slight modification. Assume the cube root of 2 is rational. Then, it may be written as a/b, where a and b are integers with no common factors. (This is possible for all nonzero rational numbers). Since a/b is the cube root of 2, its cube must equal 2. That is, (a/b)3 = 2 a3/b3 = 2 a3 = 2b3. The right side is even, so the left side must be even also, thatis, a3 is even. Since a3 is even, a is also even (because the cube of an odd number is always odd). Since a is even, there exists an integer c such that a = 2c. Now, (2c)3 = 2b3 8c3 = 2b3 4c3 = b3. The left side is now even, so the right side must be even too. The product of two odd numbers is always odd, so b3 cannot be odd; it must be even. Therefore b is even as well. Since a and b are both even, the fraction a/b is not in lowest terms, thus contradicting our initial assumption. Since the initial assumption cannot have been true, it must <span>be false, and the cube root of 2 is irrational.
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the answer to this question is C
12 is the 15% of 80
80 x 0.15 = 12
X+y=20
4x+8y=100
x=-2y+25
x=-y+20
-2y+25=-y+20
-y=-5
y=5
x=15
There are 15 true/false questions and 5 multiple choice questions