The result of rolling a number cube 7 times is a 7-digit number composed of digits 1,2,3,4,5 and 6 so that digits can repeat. The total number of possibilities is 6^7.
The number of possibilities where 4 appears exactly two times is 5^5*(7!-6!/2).
5^5 is the number of 5-digits numbers composed of digits 1,2,3,5 and 6 so that digits can repeat.
7! is the number of permutations of digits 1,2,3,4,4,5 and 6.
6! is the number of permutations of digits 1,2,3,{4,4},5 and 6.
We don't want to subtract all numbers where digits 4 appear side by side. That's why we must divide 6! by 2.
Finally, the probability is P=5^5(7!-6!/2)/7^7
Answer:
179.5 - 180.5
Step-by-step explanation:
Time is a continuous variable. The minimum sleep time per night per subject here, is given as 1 minute.
Larger sleep times could be 1.08 minutes, 2.99 minutes, and other continuous/infinite values. Remember there are 60seconds in a minute and in-between seconds, there are milliseconds. So time is a continuous variable.
In this case though, our measurement of time is given in whole number units (integers). Our precision of measurement is 1 unit. We have an observed value of 180 minutes (the first subject's sleep time). The real limits of this value are 179.5 to 180.5
Answer:
This one.
Step-by-step explanation:
A. Robert purchased a 36-inch piece of wood
Answer:
$200 : $150
Step-by-step explanation:
Sum the parts of the ratio, 4 + 3 = 7 parts
Divide the total by 7 to find the value of one part of the ratio.
$350 ÷ 7 = $50 ← value of 1 part of the ratio
4 parts = 4 × $50 = $200
3 parts = 3 × $50 = $150
