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lilai3
PLEASE HELP!!!!!!!!!!!!!!!!!!!!!!!!!!! IT's about ALIENS :) Stephen wants to learn to communicate with the aliens so he spends lots of time with them. For a week he spends at least some time with then everyday. The number of days he spends time with them after noon is one more than the number he spends time with them before noon. The number of days he spends time with them only before noon is half as many as the number he spends time with them only after noon. How many days does he spend time with the aliens both before and after noon? PLEASE USE A VENN DIAGRAM TO SHOW WORK DONE. THX!
What does this have to do with math?
Ohhhh ok nevermind Here is the definition of a venn diagram: A Venn diagram is a diagram that uses circles to illustrate the relationships among sets. Example: The Venn diagram below shows the number of grade 5 students who scored above 50% on Math, above 50% on Science, and above 50% on both Math and Science. From the Venn diagram, we learn that 16 students scored above 50% on Math, 21 students scored above 50% on Science, and 6 students scored above 50% on both Math and Science.
thanks, what a venn diagram is i just need to know how you solve this problem
Are you there? I think I have the pieces we just need to put them together
I am missing a number somewhere. I need to reread the question. there is only a total of 7 days!!
a = b + 1 (a-c)/2 = (b-c) 7 = a + b - c These are our three equations
? uhm i'm sorry i stll don't really get it... perhaps explain like what it's taking about cuz like i don't get the one more than the number stuff in the problem...
Let a = total aliens after noon Let b = total aliens before noon Let c = # of aliens in both (a-c) is only after noon (b-c) is only before noon From the problem we have 2 equations we can write. a = b + 1 (a-c)/2 = (b-c) We have 2 equations and 3 unknowns so we still can't solve. We need another equation, a total equation. 7 = a + b - c
a = b + 1 (a-c)/2 = (b-c) -> b = (a-c)/2 + c 7 = a + b - c Solve by substitution. 7 = ( b + 1) + b - c 7 = 2b + 1 - c 7 = 2[(a-c)/2 + c] - c 7 = a - c + 2c - c a = 7 b = 6 c = 6 That's a strange answer. I'm going to recheck my equations.
I don't see a mistake. a = 7 days after noon b = 6 days before noon c = 6 days both
Now I'll answer your questions
? uhm i'm sorry i stll don't really get it... perhaps explain like what it's taking about cuz like i don't get the one more than the number stuff in the problem...
@hartnn can you double check this. My answer seems unlikely although I think my math is sound
Okay we'll break down the wording first
Let a = number after noon Let b = number before noon It is saying that he spends one more day with them after noon than before noon. Say b is 10. a would have to be 11 right? So we can write this equation b + 1 = a Plugging in our example to see if it works we get 10 + 1 = 11 11=11 check
What specifically confuses you about that explanation?
We want something that represents what is happening. We use variables because we don't know what they are at first.
If I told you I was 2 years older than you what equation would you write?
a little sorry my best subject isn't math
oh like if my granpa was twice my age and i was like... 64 that would be 64 X 2 right?
really bad example because grandpas are usually not that age compared to real life