CHAPTER V.
RULE-OF-THREE
The fourth subject of treatment.
1. Salutation to that blessed Vardhamāna, who is like a (helpful) relation to (all) the three worlds, and is (resplendent) like the sun in the matter of absolute knowledge and has cast off (the taint of) all the karmas
Next we shall expound the fourth subject of treatment, viz., rule-of-three.
The rule of operation in respect thereof is as follows:--
2.[2] Here, in the rule-of-throe, Phala multiplied by Ichhā and divided by Pramāņā, becomes the (required) answer, when the Icchā and the Pramāņā are similar, (i.e., in direct proportion); and in the case of this (proportion) being inverse, this operation (involving multiplication and division) is reversed, (so as to have division in the place of multiplication and multiplication in the place of division}.
Examples relating to the former half of the above rule, i.e.,
on the direct rule-of-three
3.[3] The man who in days goes over yōjanas-give out what (distance) he (goes over) in a year and a day.
4. A lame man walks over of a krōśa together with (thereof) in 7 days. Say what (distance) he (goes over) in 3 years (at this rate ).
5. A worm goes in of a day over of an ańgula. In how many days will it reach the top of the Mēru moumtain from its bottom?
6. The man who in 3 days uses up 1 kārşāpaņas--in what time (will) he (use up) 100 purāņas along with one paņa ?
2.^ Pramāņa and Phala together give the rate, in which Phala is a quantity of the same kind as the required answer and 'Pramāņa is of the same kind as Icchā. This Icchā is the quantity about wich something is required to be found out at the given rate. For instance the problem stanza 3 here, days is the Pramāņa, yōjanas is the Phala, and 1 year and 1 day is the Icchā.
3.^ The height of the Mēru mountain is supposed to be 99,000 yōjanas or 76,032,000,000 ańgulas.
