The prisoners could do a pattern that could signal who has already been in the room. So for example, one light off, both lights off, one light on, both lights off. But with left and right lights to make the sequence last as long as possible. Then after that sequence to have the last one be the signal that everyone has been in there. I dunno this is tricky lol
Answer:
1 3/8
Step-by-step explanation:
7/8-4/5. When subtracting two fractions, we must have a common denominator. A common denominator is a factor in which goes into both 8 and 5.
1.) Common factor: 45. 45 goes into and 8 and 5. If we list out all the factors of 8 and 5, 45 will be the lowest common factor.
2.) We need to multiply by a number to get 45 for each denominator. We can a one-step equation to figure out what we need to multiply 8 by and 5 by to get 45.
X=the factor of 8 that will get us 45.
8x=45
8x/8=45/8
x=5.625.
Y=factor of 5 that will get us 45.
5y=45
5y/5=45/5
y=9.
3.) We now know that we need to multiply 8 by 5.625 and 5 by 9 in order to get 45 as the denominator for both fractions.
7/8x5.625-4/5x9
7/45-4/45.
4.) Whatever is done to the denominator must be done to the numerator.
7x5.625/45-4x9/45
39.375/45-36/45
5.) We now have common denominators, so we simple subtract the numerators ONLY. We DO NOT subtract the denominators.
39.375/45-36/45=3.375/45.
Therefore, 3.375/45 is your answer.
