S=sullivan's age
d=daughter's age
in 3 years time (s+3 and d+3)
sulivan is 3 times as old as daughter
s+3=3(d+3)
6 years ago (s-6 and d-6)
he was 6 times as old
s-6=6(d-6)
expand
s+3=3d+9
s-6=6d-36
for 2nd equation, add 6 to both sides
s=6d-30
sub 6d+30 for s in other equation
6d-30+3=3d+9
6d-27=3d+9
minus 3d both sides
3d-27=9
add 27 both sides
3d=36
divide both sides by 3
d=12
sub back
s=6d-30
s=6(12)-30
s=72-30
s=42
Mr. Sullivan is 42 now
Daughter is 12 now
Given that mean of quiz scores = 6.4 and standard deviation = 0.7
And we need to use Chebyshev's theorem to find the range in which 88.9% of data will reside.
Chebyshev's theorem states that "Specifically, no more than
of the distribution's values can be more than k standard deviations away from the mean".
That is 


k = 3
So, we want the range of values within 3 standard deviations of mean.
Hence range is [mean -3*standard deviation, mean +3*standard deviation]
= [6.4 - 3*0.7 , 6.4+3*0.7]
= [6.4 - 2.1 , 6.4+2.1] = [4.3,8.5]
33/60 in simplest form is 11/20.
Answer:
6
Step-by-step explanation: