Tutor:

New! Get regular updates about newly solved problems via algebra.com's RSS system.

---

Recent problems solved by 'rfer'

rfer answered: 12650 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 , 3690..3719 , 3720..3749 , 3750..3779 , 3780..3809 , 3810..3839 , 3840..3869 , 3870..3899 , 3900..3929 , 3930..3959 , 3960..3989 , 3990..4019 , 4020..4049 , 4050..4079 , 4080..4109 , 4110..4139 , 4140..4169 , 4170..4199 , 4200..4229 , 4230..4259 , 4260..4289 , 4290..4319 , 4320..4349 , 4350..4379 , 4380..4409 , 4410..4439 , 4440..4469 , 4470..4499 , 4500..4529 , 4530..4559 , 4560..4589 , 4590..4619 , 4620..4649 , 4650..4679 , 4680..4709 , 4710..4739 , 4740..4769 , 4770..4799 , 4800..4829 , 4830..4859 , 4860..4889 , 4890..4919 , 4920..4949 , 4950..4979 , 4980..5009 , 5010..5039 , 5040..5069 , 5070..5099 , 5100..5129 , 5130..5159 , 5160..5189 , 5190..5219 , 5220..5249 , 5250..5279 , 5280..5309 , 5310..5339 , 5340..5369 , 5370..5399 , 5400..5429 , 5430..5459 , 5460..5489 , 5490..5519 , 5520..5549 , 5550..5579 , 5580..5609 , 5610..5639 , 5640..5669 , 5670..5699 , 5700..5729 , 5730..5759 , 5760..5789 , 5790..5819 , 5820..5849 , 5850..5879 , 5880..5909 , 5910..5939 , 5940..5969 , 5970..5999 , 6000..6029 , 6030..6059 , 6060..6089 , 6090..6119 , 6120..6149 , 6150..6179 , 6180..6209 , 6210..6239 , 6240..6269 , 6270..6299 , 6300..6329 , 6330..6359 , 6360..6389 , 6390..6419 , 6420..6449 , 6450..6479 , 6480..6509 , 6510..6539 , 6540..6569 , 6570..6599 , 6600..6629 , 6630..6659 , 6660..6689 , 6690..6719 , 6720..6749 , 6750..6779 , 6780..6809 , 6810..6839 , 6840..6869 , 6870..6899 , 6900..6929 , 6930..6959 , 6960..6989 , 6990..7019 , 7020..7049 , 7050..7079 , 7080..7109 , 7110..7139 , 7140..7169 , 7170..7199 , 7200..7229 , 7230..7259 , 7260..7289 , 7290..7319 , 7320..7349 , 7350..7379 , 7380..7409 , 7410..7439 , 7440..7469 , 7470..7499 , 7500..7529 , 7530..7559 , 7560..7589 , 7590..7619 , 7620..7649 , 7650..7679 , 7680..7709 , 7710..7739 , 7740..7769 , 7770..7799 , 7800..7829 , 7830..7859 , 7860..7889 , 7890..7919 , 7920..7949 , 7950..7979 , 7980..8009 , 8010..8039 , 8040..8069 , 8070..8099 , 8100..8129 , 8130..8159 , 8160..8189 , 8190..8219 , 8220..8249 , 8250..8279 , 8280..8309 , 8310..8339 , 8340..8369 , 8370..8399 , 8400..8429 , 8430..8459 , 8460..8489 , 8490..8519 , 8520..8549 , 8550..8579 , 8580..8609 , 8610..8639 , 8640..8669 , 8670..8699 , 8700..8729 , 8730..8759 , 8760..8789 , 8790..8819 , 8820..8849 , 8850..8879 , 8880..8909 , 8910..8939 , 8940..8969 , 8970..8999 , 9000..9029 , 9030..9059 , 9060..9089 , 9090..9119 , 9120..9149 , 9150..9179 , 9180..9209 , 9210..9239 , 9240..9269 , 9270..9299 , 9300..9329 , 9330..9359 , 9360..9389 , 9390..9419 , 9420..9449 , 9450..9479 , 9480..9509 , 9510..9539 , 9540..9569 , 9570..9599 , 9600..9629 , 9630..9659 , 9660..9689 , 9690..9719 , 9720..9749 , 9750..9779 , 9780..9809 , 9810..9839 , 9840..9869 , 9870..9899 , 9900..9929 , 9930..9959 , 9960..9989 , 9990..10019 , 10020..10049 , 10050..10079 , 10080..10109 , 10110..10139 , 10140..10169 , 10170..10199 , 10200..10229 , 10230..10259 , 10260..10289 , 10290..10319 , 10320..10349 , 10350..10379 , 10380..10409 , 10410..10439 , 10440..10469 , 10470..10499 , 10500..10529 , 10530..10559 , 10560..10589 , 10590..10619 , 10620..10649 , 10650..10679 , 10680..10709 , 10710..10739 , 10740..10769 , 10770..10799 , 10800..10829 , 10830..10859 , 10860..10889 , 10890..10919 , 10920..10949 , 10950..10979 , 10980..11009 , 11010..11039 , 11040..11069 , 11070..11099 , 11100..11129 , 11130..11159 , 11160..11189 , 11190..11219 , 11220..11249 , 11250..11279 , 11280..11309 , 11310..11339 , 11340..11369 , 11370..11399 , 11400..11429 , 11430..11459 , 11460..11489 , 11490..11519 , 11520..11549 , 11550..11579 , 11580..11609 , 11610..11639 , 11640..11669 , 11670..11699 , 11700..11729 , 11730..11759 , 11760..11789 , 11790..11819 , 11820..11849 , 11850..11879 , 11880..11909 , 11910..11939 , 11940..11969 , 11970..11999 , 12000..12029 , 12030..12059 , 12060..12089 , 12090..12119 , 12120..12149 , 12150..12179 , 12180..12209 , 12210..12239 , 12240..12269 , 12270..12299 , 12300..12329 , 12330..12359 , 12360..12389 , 12390..12419 , 12420..12449 , 12450..12479 , 12480..12509 , 12510..12539 , 12540..12569 , 12570..12599 , 12600..12629 , 12630..12659, >>Next

Graphs/688004: Solve each equation for y to obtain the slope-intercept form of the equation. 4x+y=5 y= x-y=10 y= 1 solutions Answer 425461 by rfer(12654)   on 2012-12-01 18:19:14 (Show Source): You can put this solution on YOUR website! y=-4x+5 y=x-10

Mixture_Word_Problems/687663: Solve the linear equation. 7x - 3 = 18 1 solutions Answer 425316 by rfer(12654)   on 2012-11-30 21:06:13 (Show Source): You can put this solution on YOUR website! 7x=18+3 7x=21 x=21/7 x=3

Travel_Word_Problems/687693: MR.C starts running at 6:00am.He runs 15miles at 6miles perhour. What time is he done? 1 solutions Answer 425315 by rfer(12654)   on 2012-11-30 21:05:00 (Show Source): You can put this solution on YOUR website! 15/6=2.5hrs 6:00 + 2hrs 30 min=8:30am

Age_Word_Problems/687712: Three more than one-half is the same as 17 minus three times the number. 1 solutions Answer 425313 by rfer(12654)   on 2012-11-30 21:02:44 (Show Source): You can put this solution on YOUR website! 0.5x+3=17-3x 3.5x=14 x=14/3.5 x=4

Inverses/687744: i need help with this problem : 2 - 5(h + 3) = -28 1 solutions Answer 425312 by rfer(12654)   on 2012-11-30 21:00:06 (Show Source): You can put this solution on YOUR website! 2-5h-15=-28 -5h=-28+15-2 -5h=-15 h=-15/-5 h=3

Inverses/687743: i need help with this problem : 5(n + 2) = 10 1 solutions Answer 425310 by rfer(12654)   on 2012-11-30 20:58:09 (Show Source): You can put this solution on YOUR website! 5n+10=10 5n=10-10 n=0

Graphs/687142: How do you find the x and y intersect? 1 solutions Answer 425086 by rfer(12654)   on 2012-11-29 18:19:31 (Show Source): You can put this solution on YOUR website! x int is when y=0 y int is when x=0

test/687149: (3x+1/2)-(7x-4 1/2) 1 solutions Answer 425084 by rfer(12654)   on 2012-11-29 18:18:20 (Show Source): You can put this solution on YOUR website! 3x+1/2-7x+9/2= -4x+10/2=-4x+5

Numeric_Fractions/687163: how to you solve this problem: 2 2/3 divided by 1 3/5 equals what? 1 solutions Answer 425083 by rfer(12654)   on 2012-11-29 18:16:00 (Show Source): You can put this solution on YOUR website! (8/3)/(8/5)= 8/3*5/8=40/24=1 2/3

test/687183: How can I solve -x = 30? 1 solutions Answer 425079 by rfer(12654)   on 2012-11-29 18:10:57 (Show Source): You can put this solution on YOUR website! x=-30

Equations/687186: Given the geometric sequence 21870, 7290, 2430, . . . find the eighth term in the sequence. 1 solutions Answer 425078 by rfer(12654)   on 2012-11-29 18:10:02 (Show Source): You can put this solution on YOUR website! =10

Inequalities/687194: Please help ! . I need to know how to do this problem I have a test tommorow on iequalities and two step ineqalites Twenty years less than or equal to four more than Twice a number. 1 solutions Answer 425077 by rfer(12654)   on 2012-11-29 18:08:14 (Show Source): You can put this solution on YOUR website! 20 <= 2x+4

Percentage-and-ratio-word-problems/687195: what is 14% as a ratio 1 solutions Answer 425075 by rfer(12654)   on 2012-11-29 18:06:48 (Show Source): You can put this solution on YOUR website! 14/100=7/50 7:50

Probability-and-statistics/686614: A card is picked from a standard deck of 52 cards. what are the odds against and the odds in favor of drawing a red face card (King Queen Jack)? 1 solutions Answer 424854 by rfer(12654)   on 2012-11-28 18:03:34 (Show Source): You can put this solution on YOUR website! 6/52 in favor=3/26 46/52 against=23/26

Systems-of-equations/686552: what is the answer of -20 divided by x lessthan or equal to -10 1 solutions Answer 424853 by rfer(12654)   on 2012-11-28 18:01:48 (Show Source): You can put this solution on YOUR website! -20/x <= -10 -20 <= -10x -20/-10 <= x 2 >= x

Equations/686557: how do you use the distributive property on equations -5(2w+1)=25 1 solutions Answer 424852 by rfer(12654)   on 2012-11-28 17:58:37 (Show Source): You can put this solution on YOUR website! -10w-5=25 -10w=25+5 -10w=30 w=30/-10 w=-3

Permutations/686605: what is the less than sign 1 solutions Answer 424851 by rfer(12654)   on 2012-11-28 17:56:38 (Show Source): You can put this solution on YOUR website! less than <

Percentage-and-ratio-word-problems/686599: Three sevenths of the pizza was eaten.what percent of the pizza was not eaten? 1 solutions Answer 424850 by rfer(12654)   on 2012-11-28 17:56:03 (Show Source): You can put this solution on YOUR website! 4/7 not eaten 4/7=0.57=57% not eaten

Linear-systems/686517: A total of tickets were sold for the school play. They were either adult tickets or student tickets. The number of student tickets sold was two times the number of adult tickets sold . How many adult tickets were sold? 1 solutions Answer 424848 by rfer(12654)   on 2012-11-28 17:54:46 (Show Source): You can put this solution on YOUR website! need more information?

Miscellaneous_Word_Problems/686600: Maria has a piece of rope that is 3 feet long. She cuts 6 inches off the end of the rope. hat is the length of the remaining rope? Is it a multiplication? or divide? I need to now before Nov 29,2012!!!!!!!! 1 solutions Answer 424847 by rfer(12654)   on 2012-11-28 17:53:14 (Show Source): You can put this solution on YOUR website! Subtraction 3ft-6in=2ft 6in also done this way change ft to in 36-6=30in

Linear-equations/686562: what is the slope and y-intercept of the equation 4x-6y+3=0 1 solutions Answer 424845 by rfer(12654)   on 2012-11-28 17:50:35 (Show Source): You can put this solution on YOUR website! -6y=-4x-3 6y=4x+3 y=4/6x+3/6 y=2/3x+1/2 ---- slope m=2/3 y int=1/2

Average/686554: What is the ratio of correct answers to incorrect answers if the score is 80% 1 solutions Answer 424844 by rfer(12654)   on 2012-11-28 17:48:08 (Show Source): You can put this solution on YOUR website! 4/5 4:5

Linear-equations/686594: what the equation of the line that contains the point (8,0)(0,2) 1 solutions Answer 424843 by rfer(12654)   on 2012-11-28 17:46:37 (Show Source): You can put this solution on YOUR website! m=(2-0)/(0-8) m=2/-8 m=-1/4 -- y=mx+b y=-1/4x+2

Equations/686560: emily thinks of a number, n. she adds 14 to it and then square it the answer is 361. what is n? 1 solutions Answer 424841 by rfer(12654)   on 2012-11-28 17:41:45 (Show Source): You can put this solution on YOUR website! sq rt 361=19 19-14=5 n=5

Linear_Equations_And_Systems_Word_Problems/686590: Find the value of r so that the line passes through each pair of points has the given slope. (-7,2)(-8,r), m=-5. Prove your answer by graphing it. 1 solutions Answer 424840 by rfer(12654)   on 2012-11-28 17:39:46 (Show Source): You can put this solution on YOUR website! -5=(2-r)/(-7--8) -5=(2-r)/1 -5=2-r -5-2=-r r=7 --------------- proof m=(2-7)/(-7--8) m=-5/1 m=-5

Money_Word_Problems/686566: if you want to have $18,000 for a down payment on a house that you would like to buy in 7 years, how much would you need to set aside today? assume that you have access to a bank account that pays 9.25% annually compounded weekly. 1 solutions Answer 424837 by rfer(12654)   on 2012-11-28 17:36:16 (Show Source): You can put this solution on YOUR website! 18000=P(1+0.0925/52)^52+7 18000=P(1.0017788)^364 18000=P(1.909627) P=18000/1.909627 P=$9,425.92

Miscellaneous_Word_Problems/686576: If you travel 16 mi east and then 20 mi north, how far are you from your starting point? 1 solutions Answer 424835 by rfer(12654)   on 2012-11-28 17:28:13 (Show Source): You can put this solution on YOUR website! 16^2+20^2=C c=256+400 c=656 sq rt 656=25.6 miles

Average/686578: If 8 out of 20 students in a class are in band, what percent of the class is made up of students in band? 1 solutions Answer 424833 by rfer(12654)   on 2012-11-28 17:26:06 (Show Source): You can put this solution on YOUR website! 8/20=0.40=40%

Average/686581: Jennie has $300 to spend at the mall on school clothes, she spends $60 of it. What pecent of her money did she spend? What percent did she not spend? 1 solutions Answer 424832 by rfer(12654)   on 2012-11-28 17:25:16 (Show Source): You can put this solution on YOUR website! 60/300=0.20=20% b) =80%

test/686582: My homework is due tomorrow and its really confusing me! Please help! The mean of 4 test scores is 90. What is the sum of the scores? 1 solutions Answer 424831 by rfer(12654)   on 2012-11-28 17:24:05 (Show Source): You can put this solution on YOUR website! 90*4=360 360/4=90

test/685810: Replace each pair of fractions by equivalent fractions having the smallest common denominator. a. 3/10 and 7/15 b. -1/6 and 3/8 c. 6/5 and 9/20 1 solutions Answer 424591 by rfer(12654)   on 2012-11-27 12:32:35 (Show Source): You can put this solution on YOUR website! a) 9/30 14/15 b) -4/24 9/24 c) 24/20 9/20