Answer:
I think the answer is 31
Step-by-step explanation:
Answer:
1
Step-by-step explanation:
of course the answer is one but you can't write it in exponential form because a regular keyboard doesn't contain it
AVERAGE between 90 and 100%
means not including 90 and 100% but not including 90 or 100%
average=(sum of values in set)/(how many values in the set)
so
4 exams, so there are 4 values
average=(sum)/4
the sum is the known+unknwon
sum=76+99+86+x
so
90<span><</span>average and average <span><</span>100
or
90<span><</span>average<span><</span>100
lets say average=a
a=sum/number
a=(76+99+86+x)/4
90<(76+99+86+x)/4<100
90<(76+99+86+x)/4 and (76+99+86+x)/4<100
solve each for x and find intersection
90<span><</span>(76+99+86+x)/4
times 4 both sides
360<span><</span>261+x
minus 261 both sides
99<span><</span>x
(76+99+86+x)/4<u><</u>100
times 4 both sides
261+x<u><</u>400
minus 261 both sides
x<u><</u>139
so
99<u><</u>x<u><</u>139
since max score is 100
99<u><</u>x<u><</u>100
interval notaion is
[99,100]
answer is 2nd one
It works because even if the numbers are broken apart, you are still multiplying the numbers by their values, it's only different because once broken apart, it's in expanded form instead of standard form. It also makes multiplication easier since you don't have to deal with such large numbers.