Answer:
so 189(from 189.66) lower box tickets are sold and 18 upper box tickets are sold
Step-by-step explanation:
lets take "x" as the # of lower box tickets
and "y" as the number of upper box tickets
so in total the number of tickets sold was 208
so x+y=208
next, we know that each lower box ticket costs 12.50 and each upper box tickets costs 10 and the total amount of money spent was $2187.50 so:
12.5x+10y=2187.50
lets subtract "x" from both sides in first equation to find value of y
y=208-x
now substitute y in equation number 2:
12.5x-10(208-x)=2187.5
12.5x-2080+10x=2187.5
22.5x-2080=2187.5
22.5x=4267.5
x=189.666
so 189 tickets lower box tickets were purchased now, substitute 190 in equation 1 to find value of "y"
y=208-190
y=18
so 189(from 189.66) lower box tickets are sold and 18 upper box tickets are sold
This is equal to the probability that no light fail. Probability of one light not failing = 0.98.
P(no light fails) = 0.98^20 = 0.67 or 67% to nearest percent.
Count the number of positive integers less than 100 that do not contain any perfect square factors greater than 1.
Possible perfect squares are the squares of integers 2-9.
In fact, only squares of primes need be considered, since for example, 6^2=36 actually contains factors 2^2 and 3^2.
Tabulate the number (in [ ])of integers containing factors of
2^2=4: 4,8,12,16,...96 [24]
3^2=9: 9,18,....99 [11]
5^2=25: 25,50,75 [3]
7^2=49: 49,98 [2]
So the total number of integers from 1 to 99
N=24+11+3+2=40
=>
Number of positive square-free integers below 100 = 99-40 = 59
900 meters
In 0.9 move the decimal two times to the right
That makes it 900 meters