New!
Get regular updates about newly solved problems
via algebra.com's RSS system.
Recent problems solved by 'Mathtut'
Mathtut answered: 3667 problems
Jump to solutions: 0..29 , 30..59 , 60..89 , 90..119 , 120..149 , 150..179 , 180..209 , 210..239 , 240..269 , 270..299 , 300..329 , 330..359 , 360..389 , 390..419 , 420..449 , 450..479 , 480..509 , 510..539 , 540..569 , 570..599 , 600..629 , 630..659 , 660..689 , 690..719 , 720..749 , 750..779 , 780..809 , 810..839 , 840..869 , 870..899 , 900..929 , 930..959 , 960..989 , 990..1019 , 1020..1049 , 1050..1079 , 1080..1109 , 1110..1139 , 1140..1169 , 1170..1199 , 1200..1229 , 1230..1259 , 1260..1289 , 1290..1319 , 1320..1349 , 1350..1379 , 1380..1409 , 1410..1439 , 1440..1469 , 1470..1499 , 1500..1529 , 1530..1559 , 1560..1589 , 1590..1619 , 1620..1649 , 1650..1679 , 1680..1709 , 1710..1739 , 1740..1769 , 1770..1799 , 1800..1829 , 1830..1859 , 1860..1889 , 1890..1919 , 1920..1949 , 1950..1979 , 1980..2009 , 2010..2039 , 2040..2069 , 2070..2099 , 2100..2129 , 2130..2159 , 2160..2189 , 2190..2219 , 2220..2249 , 2250..2279 , 2280..2309 , 2310..2339 , 2340..2369 , 2370..2399 , 2400..2429 , 2430..2459 , 2460..2489 , 2490..2519 , 2520..2549 , 2550..2579 , 2580..2609 , 2610..2639 , 2640..2669 , 2670..2699 , 2700..2729 , 2730..2759 , 2760..2789 , 2790..2819 , 2820..2849 , 2850..2879 , 2880..2909 , 2910..2939 , 2940..2969 , 2970..2999 , 3000..3029 , 3030..3059 , 3060..3089 , 3090..3119 , 3120..3149 , 3150..3179 , 3180..3209 , 3210..3239 , 3240..3269 , 3270..3299 , 3300..3329 , 3330..3359 , 3360..3389 , 3390..3419 , 3420..3449 , 3450..3479 , 3480..3509 , 3510..3539 , 3540..3569 , 3570..3599 , 3600..3629 , 3630..3659 , 3660..3689, >>Nextpercentage/192284: How much would you owe after making the down payment for the cassette
player?
Cassette player:15%, 18$, Total Cost $ ?
Thanks for all help! 1 solutions
Answer 144348 by Mathtut(3670) on 2009-04-21 02:32:56 (Show Source):
|
test/192299: One pipe can fill a tank in 20min, while another takes 30min to fill the same tank. How long would it take the two pipes together to fill that tank? 1 solutions
Answer 144344 by Mathtut(3670) on 2009-04-21 01:38:28 (Show Source):
You can put this solution on YOUR website!1/20 of the pipe per min
:
1/30 of the pipe per min
:
together
:
(1/20+1/30)t=1
:
(3/60+2/60)t=1
:
(5/60)t=1
:
t=60/5=12 minutes
|
Polygons/192283: determine the measure of the interior angles for each of the regular polygons in the table. regular polygans Measure of interior angles
triangle 60 degrees
square
pentagon
hexagon
heptagon
thank you
1 solutions
Answer 144342 by Mathtut(3670) on 2009-04-21 01:29:08 (Show Source):
|
Geometry_Word_Problems/192235: From the top of a 200-foot cliff, the angle of depression to a boat offshore is 15 degrees. To the nearest foot, how far is the boat from the base of the cliff? 1 solutions
Answer 144295 by Mathtut(3670) on 2009-04-20 20:43:47 (Show Source):
You can put this solution on YOUR website!opposite over ajacent problem so we will deal with tangent
:
tan 15=200/x........where x is the distance from the boat to the base of cliff
:
0.26794919243112 x=200
:
x=746 ft (the nearest foot)
|
Linear-systems/192256: This question is from textbook Intermediate Algebra
An office has some 20 cent stamps and some 28 cent stamps. All together the office has 140 stamps for a total value of $31.20. How many of each stamp does the office have?
my try:
Stamps Number Value Total Value
20 cent x .20 .20x
28 cent 140 -x .28 .28(140-x)
.20x + .28(140-x) = 31.20
.20x + 39.20 - .28x = 31.20
.08x + 39.20 = 31.20
-.08x = -8.00
x = 1
WRONG? What am I doing wrong?? Help!
1 solutions
Answer 144294 by Mathtut(3670) on 2009-04-20 20:38:51 (Show Source):
You can put this solution on YOUR website!let the number of 20 cent and 28 cent stamps by x and y respectively
:
x+y=140........eq 1
.2x+.28y=31.2..eq 2
:
rewrite eq 1 to x=140-y and plug it into eq 2
:
.2(140-y)+.28y=31.2
:
28-.2y+.28y=31.2
:
.08y=3.2
:
y=40 (28 cent stamps)
:
x=140-y=140-40=100 (20 cent stamps)
|
Probability-and-statistics/192226: P(G) = 0.5, P(H) = 0.6, and P(G|H′) = 0.25. Find P(G and H'), P(G or H), and P(P(G|H). I know that the answers are 1/10, 7/10, and 2/3 respectively, I'm just not sure how to get them. Thank you!! 1 solutions
Answer 144290 by Mathtut(3670) on 2009-04-20 20:30:43 (Show Source):
You can put this solution on YOUR website!The first problem is:
:
since P(H)=.6 we know that P(H')=.4
:
P(G|H')=P(G and H')/P(H')
:
.25=P(G and H')/.4)---->P(G and H')=.4(.25)=.1 or 1/10
:
|
real-numbers/192214: In a local area the government intends to reduce the coyote population by 10% each year. If the coyote population is now estimated to be 3,000, how many coyotes will remain after 3 years? 1 solutions
Answer 144282 by Mathtut(3670) on 2009-04-20 20:02:15 (Show Source):
|
Graphs/192237: a line in the Cartesian plane passes through the points (-2,4) and (2,-1). what is the rise and the run of the line? I got run is4 and rise is 5 is it corect? 1 solutions
Answer 144272 by Mathtut(3670) on 2009-04-20 19:40:12 (Show Source):
You can put this solution on YOUR website!rise is -1-4=-5 for which the run would be 2-(-2)=4 or the rise is 4-(-1)=5 for which the run is -2-2=-4
:
in both cases the slope is -5/4
|
Linear-systems/192182: Please help me solve...
A women has $7000,part is invested for one year paying 7% interest and the remaining amount in a fund paying 9%. After a year total interest on the 2 investments is $540. How much is invested at each rate? 1 solutions
Answer 144224 by Mathtut(3670) on 2009-04-20 15:55:17 (Show Source):
You can put this solution on YOUR website!let amounts invested at 7% and 9% be x and y respectively
:
x+y=7000...........eq 1
.07x+.09y=540......eq 2
:
rewrite eq 1 to x=7000-y and plug this into eq 2
:
.07(7000-y)+.09y=540
:
490-.07y+.09y=540
:
.02y=50
:
y=2500 dollars invested at 9%
:
x=7000-y=7000-2500=4500 dollars invested at 7%
|
Equations/192161: I home school and I am stuck on a problem.
all the information the directions give me is "solve each equation"
The worksheet is on radical equations' graphs, and complex numbers
Please help me solve this equation:
(2x-3)^2=-24 1 solutions
Answer 144196 by Mathtut(3670) on 2009-04-20 14:14:15 (Show Source):
|
Trigonometry-basics/192147: This question is from textbook
Find the vertex, focus and directrix of the parabola. [NOTE: fractions must be reduced and mixed numbers have to be reported as improper fractions]
y = x2 - 20x + 10 1 solutions
Answer 144194 by Mathtut(3670) on 2009-04-20 14:09:32 (Show Source):
|
|