Answer:
probability that he or she will answer at least 4 problems correctly = 0.5
Step-by-step explanation:
probability that he or she will answer at least 4 problems correctly is given as;
P (at least 4 correctly) = P (exactly 4 correctly) + P (all 5 correctly)
Since there are 10 problems. 4 is from the 7 problems chosen and 1 is from the 3 problems we can't figure out. Thus, P(exactly 4 correctly) = 7C4 x 3C1
Thus, P (at least 4 correctly) = [ (7C4) x (3C1) ] / (10C5)] + [(7C5)/(10C5)]
= [(35 x3)/252 ] + [21/252]
= [ 105/252 ] + [ 21/252 ]
= 126 / 252
= 0.5
My answer is 8 5/9
First, you have to multiply the denominators to get your least common denominator.
Second, you have to multiply the numerators and the denominators together to get two different fractions with the same denominator. You should get 9 3/9 and 1 6/9.
Your answer should be 8 5/9
They all end up being 1
100% = 1
4/4 = 1
1.000 = 1
4i = b
6(i-6) = b-6
6(i-6) = 4i - 6
6i - 36 = 4i - 6
2i - 36 = -6
2i = 30
i = 15 years old
b = 60 years old
Check:
15 * 4 = 60
9 * 6 = 54 :)
