Math questions fractions and other stuff!!!!?
1.)It takes Sally 1 3/4 hours to mow her lawn if he mows the lawn 13 time during the summer and he increases his speed and gets faster at mowing each time by 5 minutes, how much time will it take him to mow the lawn on the 13th time that summer?
2.) 3 2/3 + (-5 3/4)
----------------------
7 3/4 + (-1 1/8)
I got 165/-14 (simplified) PLZ actually do the question cuz im pretty sure I got it wrong
3.) Cost of I phone is $375. Rate of discount for the phone is 15% with 5% sales tax. And if they took that money and instead of buying the IPhone They invested it in a money market account at the bank at 4% for 5 years compunded anually then what would you have after 5 years?
I just need the formula cuz my teacher taught me a very hard one
4.) Solve for x.
2^2+ 4(x+-6) = 4- 7(5x-9)+ 6x - 37
I really tried on this question but i can't figure it out~~~~~~~~~~!
No guarantees - Here are my stabs:
1) 1 3/4 hr first mowing
13 total mowings
5 minutes less each mowing
in 12 mowings, time reduced by 5 min/ea
(5min*12mowings)=50min tolal min saved by 13th
convert hrs to minutes:
1 3/4hr = 60min + 45min=105min
(105min, 1st mow)-(5*12min saved, 13th mow)
= 45 minutes taken by 13th mowing
2) [(3+2/3) + (-5 + -3/4)]/[(7+3/4) + (-1 + -1/8)]
[(3+2/3-5-3/4)]/[(7+3/4-1-1/8)]
[-2 + 2/3 - 3/4]/[6 + 3/4 - 1/8)]
[-2 + 4/12 - 9/12] / [6 + 12/16 - 2/16]
[-2 + -5/12] / [6 + 10/16]
[-24/12 + -5/12] / [96/16 + 10/16]
[-29/12] / [106/16]
[-29/12] * [16/106]
[-29/3] * [4/106]
[-29/3] * [2/53]
[-29*2] / [3*53]
[-58] / [159]
4) 2^2 + 4(x + -6) = 4 - 7(5x - 9) + 6x -37
4+ (4x - 24) = 4 + (-35x + 63) + 6x -37
4x - 20 = 67 - 29x - 37
4x = 20 + 67 -29x -37
4x = 87 - 29x - 37
4x + 29x = 87 - 37
33x = 50
33x/33 = 50/33
x = 50/33
x = 1 17/33
3) I don't have the cumulative formula; it isn't especially nice as I remember it. However, this is what I got for the amount of money paid for the phone:
(375 * .85) is what you pay after the 15% discount
(375 * .05) is the amount of 5% tax on the full phone price
( (375 *.85) *.05) is the amount of 5% tax on the discounted amount
NOTE: In part it depends upon which value you pay tax on
If the full amount is taxed, you pay the following for the phone:
(375 * .85) + (375 * .05)
If you are only taxed for the discounted amount:
(375 * .85) + ( (375 *.85) *.05)
Texas Tax Sales Video
