https://calculadorafracciones.com/en/blog/feed.xmlFraction blogPick a fraction article by what you need: prepare a lesson, practice, understand a procedure, or read a curiosity, with one example of each.2026-10-24T00:00:00ZCalculadora de Fraccioneshttps://calculadorafracciones.com/en/blog/1-to-4-dilution-ratio/1:4 dilution: one quarter or one fifth?2026-10-05T00:00:00Z2026-10-05T00:00:00ZWhat 1:4 means on a dilution label and how much concentrate and water go into 1 L, 750 mL or 2 L. Includes the "1 in 4" reading, which changes the result.https://calculadorafracciones.com/en/blog/17-camels-problem/The 17 Camels Puzzle, Explained with Fractions2026-10-05T00:00:00Z2026-10-05T00:00:00ZThree brothers inherit 17 camels: one half, one third, and one ninth. A borrowed camel gives them 9, 6, and 2. The key: 1/2 + 1/3 + 1/9 = 17/18.https://calculadorafracciones.com/en/blog/50-30-20-rule-fractions/The 50/30/20 rule explained with fractions2026-10-05T00:00:00Z2026-10-24T00:00:00ZWork out the 50/30/20 rule as fractions of a total: 1800 splits into 900, 540 and 360. Check the parts add up to the total and adapt it to other percentages.https://calculadorafracciones.com/en/blog/aspect-ratio-16-9/Aspect ratio 16:9: how to simplify resolutions2026-10-05T00:00:00Z2026-10-05T00:00:00ZSimplify 1920×1080 to 16:9 with the greatest common divisor, find an image's missing height, and see why 2560×1080 is 64:27 and not 21:9.https://calculadorafracciones.com/en/blog/average-speed-round-trip/Average round-trip speed: 60 out, 40 back2026-10-05T00:00:00Z2026-10-05T00:00:00ZDriving 60 mph out and 40 mph back gives an average speed of 48 mph, not 50. Find the average of two speeds with a table, and the case where it cannot be done.https://calculadorafracciones.com/en/blog/bicycle-gear-ratios/Bicycle gear ratio: chainrings and sprockets2026-10-05T00:00:00Z2026-10-24T00:00:00ZWith a 50-tooth chainring and a 20-tooth sprocket, the wheel turns 5/2 times per pedal revolution. Work out development in meters and speed in km/h at 90 rpm.https://calculadorafracciones.com/en/blog/calculate-test-grade/How to calculate a test grade with fractions2026-10-05T00:00:00Z2026-10-05T00:00:00ZWork out a test grade with fractions: points over the maximum, times the scale. Also weighted averages, penalties for wrong answers, letter grades and rounding.https://calculadorafracciones.com/en/blog/create-fraction-worksheets/Fraction Worksheets with Answer Keys: Model and How to Build One2026-10-05T00:00:00Z2026-10-24T00:00:00ZA 12-problem fraction worksheet with a key: 6 on equivalence, 4 sums in sixths and 2 word problems. How to order the difficulty and which answers to accept.https://calculadorafracciones.com/en/blog/diophantus-riddle/Diophantus’ riddle: the age that solves his epitaph2026-10-05T00:00:00Z2026-10-05T00:00:00ZThe epitaph of Diophantus is solved with one equation and the least common multiple 84. The stages add 14, 7, 12, 5, 42 and 4 years, so the age is x = 84.https://calculadorafracciones.com/en/blog/fraction-classroom-activities/Five fraction activities for the classroom2026-10-05T00:00:00Z2026-10-05T00:00:00ZPaper strips, tape, a recipe card, a wrong sum and bars make a 40-minute fraction session, with sample answers to discuss.https://calculadorafracciones.com/en/blog/fractions-in-music/Fractions in Music: Note Values, Dots, and Time Signatures2026-10-05T00:00:00Z2026-10-05T00:00:00ZHow long a dotted quarter note lasts, how to add note values until a measure is full, and why two measures of the same length can sound different.https://calculadorafracciones.com/en/blog/fractions-in-photography/Fractions in Photography: Shutter Speed and f-Number2026-10-05T00:00:00Z2026-10-05T00:00:00ZShutter speed is a fraction of a second: 1/125 and 1/60. The f-number is a ratio of focal length to diameter, and f/4 lets in 1/4 of the light.https://calculadorafracciones.com/en/blog/fractions-in-the-news/"One in four" as a percentage: fractions in the news2026-10-05T00:00:00Z2026-10-05T00:00:00Z"1 in 4" is 1/4, or 25%. How to compare 3/8 with 2/5 and tell percentage points, relative change and absolute risk apart in a headline.https://calculadorafracciones.com/en/blog/fractions-that-approximate-pi/Which fractions approximate π, and which one to use2026-10-05T00:00:00Z2026-10-05T00:00:00ZCompare the best-known and other fractions that approximate π, with their error and the denominator you need, and see where they come from.https://calculadorafracciones.com/en/blog/gold-karats-fractions/What 18-karat gold means: 18/24 = 3/4 = 75%2026-10-05T00:00:00Z2026-10-05T00:00:00Z18-karat gold is 18/24 = 3/4 = 75% pure gold. Learn to convert karats to a fraction, a percentage and fineness, and to find the grams of gold in a piece.https://calculadorafracciones.com/en/blog/golden-ratio-fibonacci-fractions/The golden ratio and Fibonacci fractions2026-10-05T00:00:00Z2026-10-05T00:00:00ZThe Fibonacci ratios 3/2, 5/3 and 13/8 close in on φ ≈ 1.618034 from above and below. Table, continued fraction [1; 1, 1, …] and exact differences.https://calculadorafracciones.com/en/blog/help-with-fractions/How to Help a Child with Fractions Without Doing the Homework2026-10-05T00:00:00Z2026-10-24T00:00:00ZA table of common wrong answers, the likely idea behind each, the question that helps the child find the mistake, and how to check the correction.https://calculadorafracciones.com/en/blog/history-of-fractions/History of fractions: from Egypt to the fraction bar2026-10-05T00:00:00Z2026-10-05T00:00:00ZHow a fraction was written in Egypt, Babylon, India and Europe: what is known about the Rhind papyrus, base 60, the fraction bar and the ÷ sign.https://calculadorafracciones.com/en/blog/interpret-fraction-solution-steps/How to read the steps of a fraction solution2026-10-05T00:00:00Z2026-10-05T00:00:00ZRead a fraction solution step by step: common denominator, operation, sign and reduction. How to find the first false equality and fix it.https://calculadorafracciones.com/en/blog/leap-years-fractions/Why leap years exist: the calendar fraction2026-10-05T00:00:00Z2026-10-24T00:00:00ZLeap years exist since the solar year lasts ≈365.2422 days: the Julian calendar uses 365 + 1/4, the Gregorian 365 + 97/400. Why 1900 and 2100 aren't leap years.https://calculadorafracciones.com/en/blog/margin-vs-markup/Margin vs. markup: why one 25% is not another 25%2026-10-05T00:00:00Z2026-10-05T00:00:00ZMarkup is figured on cost and margin on price: a 25% markup leaves a 20% margin. Exact conversions between the two and a worked pricing example.https://calculadorafracciones.com/en/blog/parallel-resistors-fractions/Parallel resistors: formula and sum of reciprocals2026-10-05T00:00:00Z2026-10-05T00:00:00ZHow to find parallel resistance with fractions: add the reciprocals, then flip the sum. 6 Ω and 3 Ω give 2 Ω, and three branches work the same way.https://calculadorafracciones.com/en/blog/remove-tax-from-price/How to remove tax from a price: divide, do not subtract2026-10-05T00:00:00Z2026-10-05T00:00:00ZTo take tax out of a price that includes it, divide by 1 + r/100. At 8%, $54.00 gives a base of $50.00; factor table, rounding and a discount before tax.https://calculadorafracciones.com/en/blog/spanish-fraction-names/Eleventh or one eleventh? How fractions are named in English2026-10-05T00:00:00Z2026-10-24T00:00:00ZOne eleventh is 1/11, one of eleven equal parts; the eleventh is a position. How to read 3/11 and 7/12, why half and quarter are special, a third vs the third.https://calculadorafracciones.com/en/blog/square-root-of-2-not-a-fraction/Why the square root of 2 is irrational: the proof2026-10-05T00:00:00Z2026-10-05T00:00:00ZProof by contradiction that the square root of 2 is not a rational number, with the closest simple fractions 3/2, 7/5, 17/12, 41/29 and 99/70.https://calculadorafracciones.com/en/blog/successive-discounts/Successive discounts: why 20% + 20% is not 40%2026-10-05T00:00:00Z2026-10-05T00:00:00ZWork out two discounts in a row by multiplying factors: on $60, two 20% cuts leave $38.40. Compare with a single 40% cut, half off the second item and 3-for-2.https://calculadorafracciones.com/en/blog/why-0-1-plus-0-2/Why 0.1 + 0.2 is not 0.3 on a computer2026-10-05T00:00:00Z2026-10-05T00:00:00Z0.1 and 0.2 are stored as approximate binary fractions, so 0.1 + 0.2 prints 0.30000000000000004 while the exact sum 1/10 + 2/10 = 3/10 is different.https://calculadorafracciones.com/en/blog/why-60-minutes/Why an hour has 60 minutes2026-10-05T00:00:00Z2026-10-05T00:00:00Z60 has 12 divisors and 100 only 9, so fractions of an hour come out as whole minutes. What is known about the origin in Mesopotamia.https://calculadorafracciones.com/en/blog/why-fractions-are-hard/Why fractions are hard: the whole-number bias2026-10-05T00:00:00Z2026-10-05T00:00:00ZSix whole-number beliefs that break with fractions, each with a counterexample, and how the number line and estimating help.https://calculadorafracciones.com/en/blog/zeno-half-series/Zeno's paradox with fractions: 1/2 + 1/4 + 1/8 + … = 12026-10-05T00:00:00Z2026-10-05T00:00:00ZThe series 1/2 + 1/4 + 1/8 + … adds up to 1 and answers Zeno's paradox: the partial sums 1/2, 3/4, 7/8 and 15/16 approach 1 as a limit.