What is Ratio: Definition and 1000 Discussions

In mathematics, a ratio indicates how many times one number contains another. For example, if there are eight oranges and six lemons in a bowl of fruit, then the ratio of oranges to lemons is eight to six (that is, 8∶6, which is equivalent to the ratio 4∶3). Similarly, the ratio of lemons to oranges is 6∶8 (or 3∶4) and the ratio of oranges to the total amount of fruit is 8∶14 (or 4∶7).
The numbers in a ratio may be quantities of any kind, such as counts of people or objects, or such as measurements of lengths, weights, time, etc. In most contexts, both numbers are restricted to be positive.
A ratio may be specified either by giving both constituting numbers, written as "a to b" or "a∶b", or by giving just the value of their quotient a/b. Equal quotients correspond to equal ratios.
Consequently, a ratio may be considered as an ordered pair of numbers, a fraction with the first number in the numerator and the second in the denominator, or as the value denoted by this fraction. Ratios of counts, given by (non-zero) natural numbers, are rational numbers, and may sometimes be natural numbers. When two quantities are measured with the same unit, as is often the case, their ratio is a dimensionless number. A quotient of two quantities that are measured with different units is called a rate.

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  1. H

    MHB Ratio of the Area of Similar Polygons

    Two corresponding sides of two similar polygons have lengths 3 and 7. the perimeter of the larger polygon is 91 cm. What is the perimeter of the smaller polygon? What is the ratio of their areas? I believe I have found the perimeter of the smaller polygon (39), but I can't figure out the areas...
  2. M

    MHB Find the ratio of Alan and Jenny's speeds

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  3. F

    Ratio Test for Finding the 1(circled part) - Understanding the Process

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  4. K

    A Equilibrium liquid-gas ratio in a binary mixture

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  5. I

    MHB Expressing a ratio as a fraction, decimal and percentage

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  6. Z

    Ratio of Forces by from Tennis Serve?

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  7. L

    How to show how speed varies with incline, and with Gear ratio

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  8. K

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  9. neilparker62

    Why Does the Proton-Electron Mass Ratio Diverge from Direct Division?

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  10. S

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  11. L

    Maximum ratio of calcium, atp hydrolysis

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  12. M

    MHB Ratio of fundamental frequencies

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  13. O

    Thermoelectric Modules: Heat/Cold Ratio for Voltage

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  14. W

    Calculating the charge to mass ratio

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  15. C

    Ratio of effective and average voltage

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  16. irhum31

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  17. I

    I Proton / electron mass ratio equation

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  18. fatgianlu

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  19. DrYassine

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  20. G

    MHB What is the ratio of complex numbers in the form of a question?

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  21. sunrah

    Ratio of time dilation relation in different potentials

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  22. C

    Signal to noise ratio and uncertainty in magnitude

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  23. Likith D

    How did Mendel derive the phenotypic ratio of the pea plant?

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  24. E

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  25. D

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  26. D

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  27. D

    Intr rocket science: How calculate mass ratio and propellant

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  28. A

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  29. Albert1

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  30. C

    Finding Reactance Ratio in Electrical Resonance

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  31. T

    Time dependence of the Ratio Hubble length to scale factor

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  32. Karan Punjabi

    Explaining the Proton-to-Electron Ratio in the Periodic Table

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  33. J

    Finding volume ratio between 2 vessels using ideal gases

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  34. moenste

    Ratio of potassium atoms to calcium atoms in 1 hour

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  35. J

    Ratio of atoms in different laser levels

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  36. Z

    Calculate Young's modulus and Poisson's ratio

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  37. J

    Slenderness ratio, mode of failure

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  38. P

    MHB Yonglie's question via email about ratio test

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  39. T

    Ratio of two masses connected by pulley

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  40. G

    What is the dating ratio of a rock sample that contains 87Rb and 86Sr?

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  41. Carlko26

    Turbocharger: Mass flow rate and pressure ratio

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  42. terryds

    Vector divide with negative ratio?

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  43. P

    Ratio control for multiple streams

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  44. Albert24

    Ratio of the Magnitude of gravitational force?

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  45. 1729

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  46. A

    Identification of a ratio using Refractive indices (RESOLVED)

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  47. S

    MHB Black Plastic Lid - Measurement Ratio

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  48. ChrisVer

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  49. Albert1

    MHB Find the Ratio of $\overline{BD}: \overline{CD}$ in $\triangle ABC$

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  50. Priyadarshini

    A Ball Is Thrown Vertically Upwards, Find The Ratio of PE to KE

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