Please help! I have a complicated word problem.
In a certain town, the inches of rainfall, x, on a certain day is described by two statements: If 3 times the rainfall is increased by 2, the rainfall is still less than 26 inches. 5 plus twice the rainfall is greater than 11 inches. Part A: Create a compound inequality to represent the rainfall range. (3 points) Part B: Can the rainfall in this town be 4 inches? Justify your answer by solving the inequalities in Part A. (3 points) Part C: The average rainfall in another town is 5 inches but the actual rainfall is within 4 inches of the average. Write and solve an inequality to find the range of rainfall height in this town. (4 points)
We know that rainfall on that particular day is x inches. Let's try to create inequality for the first statement: If 3 times the rainfall is increased by 2, the rainfall is still less than 26 inches. Can you try?
@micahpkay ???
Sorry about that. I accidentally exited my window with a bunch of tabs open and it took forever to load again.
3x + 2 < 26
yes, correct :) now how about 5 plus twice the rainfall is greater than 11 inches. ?
2x + 5 > 11
But what do I do with these expressions?
good. could you solve them ?
those are inequalities, you can isolate 'x' from each of them
*equations
3x + 2 - 2 < 26 - 2 3x < 24 3x/3 < 24/3 x < 8
2x + 5 > 11 2x + 5 - 5 > 11 - 5 2x > 6 2x/2 > 6/2 x > 3
Correct?
yes! so x can take any value which is >3 and less than 8 so, can x take the value of 4 ?
Yes.
Would I write it as 3 < x < 8?
yes,
So is "3 < x < 8?" the answer to Part A?
yes, yes it is!
Sorry about leaving. Are you still there?
yes
Okay.
Can you help me on Part C?
actual rainfall is within 4 inches of the average (=5) so, let the actual rainfall be 'x' x is not more than 4 inches greater than 5 or x is not less than 4 inches lesser than 5 can you try to make an equality ?
no... 5 is avg. and x can be only 4 inches far from 5 so, x-4 < 5 or x+4 >5
So do I simplify these inequalities?
yes, and then you can prepare a compound inequality from it :)
x - 4 < 5 x - 4 + 4 < 5 + 4 x < 9
yes
x + 4 > 5 x + 4 - 4 > 5 - 4 x > 1
yes
So now what?
x> 9 or x<1 try to combine this ?
9 < x < 1
How is that even possible??
oh wait, its x<9 not x>9 that you found so, combine x<9 and x>1
Yeah. That's what I thought. lol
1 < x < 9
yes, it is :)
Okay thanks. :) PS: I found x < 9, not x > 9.
yeah, yes.
The instructions say to write AND solve the inequality. How do I "solve" it?
you already solved it, solve means to isolate x write the inequality : x-4 < 5 or x+4 >5 solve it : ..... 1 < x < 9
Oh, okay.
Thanks for helping me! You deserve 10 medals! lol
:)
you're most welcome ^_^ you understood it, thats my medal :)
How sweet. I'm crying. jk :)
It's 5:00 in the morning where I live. Time for bed. lol
ohh! have a good night and sweet dreams :)
You too. Cya!
Final Answer Part A: 3x + 2 < 26 3x + 2 - 2 < 26 - 2 3x < 24 3x/3 < 24/3 x < 8 _____ 2x + 5 > 11 2x + 5 - 5 > 11 - 5 2x > 6 2x/2 > 6/2 x > 3 _____ If "x" is greater than 3 but less than 8, I can write the compound inequality shown below. 3 < x < 8 Part B: Yes, it can be 4 inches because 4 is greater than 3 and less than 8. I already solved the inequalities in Part A. Part C: x - 4 < 5 or x + 4 > 5 _________________________ x - 4 < 5 x - 4 + 4 < 5 + 4 x < 9 _____ x + 4 > 5 x + 4 - 4 > 5 - 4 x > 1 _____ Since "x" is greater than 1 but less than 9, I can write the compound inequality shown below. 1 < x < 9
seems good :)
Thanks.
Okay. I'm going to bed now for sure. Bye!
bye :) sleep tight.
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