Aquatics Unlimited: Articles: What Are the Odds?
Image 1
Image 2
Image 3

What Are the Odds?

for the week of 1/22/98

OddsIt has long been held that one of the best ways to obtain mated pairs of fish is to purchase a group of young fish and rear them to maturity. But how many fish should you buy to be assured of ending up with at least one of each sex?

The table at right gives the odds for groups of 1 to 10 juveniles, ranging from 0% for a "group" of 1 to 99.8% for a ten-pack. To better understand what these figures mean, assume 100 hobbyists each purchased 2 fish; 50 of them would likely end up with a male and female, while the other 50 would end up with both of the same sex. Had they all purchased 8 fish originally, 99 would have at least one pair, and only one would be disappointed to end up with all of the same sex. A 10 fish purchase is so near a sure thing that only 1 in 500 hobbyists would likely miss out. The formula for even larger numbers of fish is:

Percent Odds = 100-(1/2^(number of fish - 1))

These figures assume that the species in question produces roughly half males and half females and that the specimens are selected completely at random. A common practice of picking the biggest or most colorful fishes might drastically tilt the odds toward one sex.

Submitted by: Jim Kostich


"Tip of the week" appeared regularly in 1999 and 2000.

Copyright © 1998 Aquatics Unlimited
All rights reserved.

Local Specials

Through Sunday, 5-28-17

Fish on East Wall 20% OFF!***

2.5 black tank $12

5.5 black tank $14

10 black tank $15

20H black tank $29

20L black tank $29

29 black tank $45

10 Power Priced LED Kit $54.99**

20 Power Priced LED Kit $74.99**

29 Power Priced LED Kit $94.99**

55 Power Priced LED Kit $164.99**

REWARDS account may be required for special pricing. You may sign up and use the special pricing the same day!

* = SPECIAL ORDER; 50% deposit required

** = while supplies last

*** = specially marked tanks only; selection may vary during the sale

Aquatics Unlimited | 3550 S. 108th Street | Greenfield, WI 53228
Monday-Saturday 10:00 a.m. - 9:00 p.m., Sunday 10:00 a.m. - 6:00 p.m. | Phone: 414-543-2552 | Fax: 414-543-4929