| decade | 1 dec | 2 dec | 3 dec | 4 dec | 5 dec | 6 dec | 7 dec | 8 dec | 9 dec | 10 dec | 11 dec | 12 dec | 13 dec | 14 dec | 15 dec | 16 dec | 17 dec | 18 dec | 19 dec | 20 dec | 21 dec | 22 dec | 23 dec | 24 dec | 25 dec | 26 dec | 27 dec | 28 dec | 29 dec | 30 dec | 31 dec | 32 dec | 33 dec | 34 dec | 35 dec | 36 dec | 37 dec | 38 dec | 39 dec | 40 dec | 41 dec | 42 dec | 43 dec | 44 dec | 45 dec | 46 dec | 47 dec | 48 dec | 49 dec | 50 dec | 51 dec | 52 dec | 53 dec | 54 dec | 55 dec | 56 dec | 57 dec | 58 dec | 59 dec | 60 dec | 61 dec | 62 dec | 63 dec | 64 dec | 65 dec | 66 dec | 67 dec | 68 dec | 69 dec | 70 dec | 71 dec | 72 dec | 73 dec | 74 dec | 75 dec | 76 dec | 77 dec | 78 dec | 79 dec | 80 dec | 81 dec | 82 dec | 83 dec | 84 dec | 85 dec | 86 dec | 87 dec | 88 dec | 89 dec | 90 dec | 91 dec | 92 dec | 93 dec | 94 dec | 95 dec | 96 dec | 97 dec | 98 dec | 99 dec | 100 dec |
| fortnight | 260.8872851 fn | 521.7745701 fn | 782.6618552 fn | 1,043.5491402 fn | 1,304.4364253 fn | 1,565.3237103 fn | 1,826.2109954 fn | 2,087.0982804 fn | 2,347.9855655 fn | 2,608.8728505 fn | 2,869.7601356 fn | 3,130.6474206 fn | 3,391.5347057 fn | 3,652.4219907 fn | 3,913.3092758 fn | 4,174.1965608 fn | 4,435.0838459 fn | 4,695.9711310 fn | 4,956.8584160 fn | 5,217.7457011 fn | 5,478.6329861 fn | 5,739.5202712 fn | 6,000.4075562 fn | 6,261.2948413 fn | 6,522.1821263 fn | 6,783.0694114 fn | 7,043.9566964 fn | 7,304.8439815 fn | 7,565.7312665 fn | 7,826.6185516 fn | 8,087.5058366 fn | 8,348.3931217 fn | 8,609.2804067 fn | 8,870.1676918 fn | 9,131.0549769 fn | 9,391.9422619 fn | 9,652.8295470 fn | 9,913.7168320 fn | 10,174.6041171 fn | 10,435.4914021 fn | 10,696.3786872 fn | 10,957.2659722 fn | 11,218.1532573 fn | 11,479.0405423 fn | 11,739.9278274 fn | 12,000.8151124 fn | 12,261.7023975 fn | 12,522.5896825 fn | 12,783.4769676 fn | 13,044.3642526 fn | 13,305.2515377 fn | 13,566.1388228 fn | 13,827.0261078 fn | 14,087.9133929 fn | 14,348.8006779 fn | 14,609.6879630 fn | 14,870.5752480 fn | 15,131.4625331 fn | 15,392.3498181 fn | 15,653.2371032 fn | 15,914.1243882 fn | 16,175.0116733 fn | 16,435.8989583 fn | 16,696.7862434 fn | 16,957.6735284 fn | 17,218.5608135 fn | 17,479.4480985 fn | 17,740.3353836 fn | 18,001.2226687 fn | 18,262.1099537 fn | 18,522.9972388 fn | 18,783.8845238 fn | 19,044.7718089 fn | 19,305.6590939 fn | 19,566.5463790 fn | 19,827.4336640 fn | 20,088.3209491 fn | 20,349.2082341 fn | 20,610.0955192 fn | 20,870.9828042 fn | 21,131.8700893 fn | 21,392.7573743 fn | 21,653.6446594 fn | 21,914.5319444 fn | 22,175.4192295 fn | 22,436.3065146 fn | 22,697.1937996 fn | 22,958.0810847 fn | 23,218.9683697 fn | 23,479.8556548 fn | 23,740.7429398 fn | 24,001.6302249 fn | 24,262.5175099 fn | 24,523.4047950 fn | 24,784.2920800 fn | 25,045.1793651 fn | 25,306.0666501 fn | 25,566.9539352 fn | 25,827.8412202 fn | 26,088.7285053 fn |
A decade is a period of ten years. The word is derived (via French and Latin) from the Ancient Greek: δεκάς (/ðɛkˈɑːs/, transliteration=dekas), which means a group of ten.
| Name of unit | Symbol | Definition | Relation to SI units | Unit System |
|---|---|---|---|---|
| decade | dec | ≡ 10 years (10 y) | = 315 569 260 s | Metric system SI |
| decades | fortnights | decades | fortnights |
|---|---|---|---|
| 1 | = 260.88728505291 | 6 | = 1565.3237103175 |
| 2 | = 521.77457010582 | 7 | = 1826.2109953704 |
| 3 | = 782.66185515873 | 8 | = 2087.0982804233 |
| 4 | = 1043.5491402116 | 9 | = 2347.9855654762 |
| 5 | = 1304.4364252646 | 10 | = 2608.8728505291 |
A fortnight is a unit of time equal to 14 days (2 weeks). The word derives from the Old English: fēowertyne niht, meaning "fourteen nights".
| Name of unit | Symbol | Definition | Relation to SI units | Unit System |
|---|---|---|---|---|
| fortnight | fn | ≡ 2 wk | = 1.2096 Ms | Metric system SI |
| fortnights | decades | fortnights | decades |
|---|---|---|---|
| 1 | = 0.0038330729678803 | 6 | = 0.022998437807282 |
| 2 | = 0.0076661459357607 | 7 | = 0.026831510775162 |
| 3 | = 0.011499218903641 | 8 | = 0.030664583743043 |
| 4 | = 0.015332291871521 | 9 | = 0.034497656710923 |
| 5 | = 0.019165364839402 | 10 | = 0.038330729678803 |
| decades | fortnights |
|---|---|
| 1 | = 260.8872851 |
| 0.0038331 | = 1 |
| Symbol | Definition |
|---|---|
| ≡ | exactly equal |
| ≈ | approximately equal to |
| = | equal to |
| digits | indicates that digits repeat infinitely (e.g. 8.294 369 corresponds to 8.294 369 369 369 369 …) |