In the equation,  p= 0.15b + 0.93k, p 
represents the purchase price in dollars for buying b bananas 
and k kiwi fruit.

An ordered pair will be represented by (k,b). Describe what set 
of numbers will give actual solutions.ie; Integer, Rational, 
Whole, Natural.

It could not be "integer", because negative integers like -3
or -5 are rational numbers, and you cannot have negative numbers
of fruit.  So we rule out "Integer".

It could not be "rational" because rational numbers include all
common fractions like 1/2, 2/3, 7/8, and we don't buy fractions
of fruits.  Rational numbers also contain negative integers and
negative fractions, all the mor reason why it could not be
"rational".  So we rule out "Rational".

It could not be "whole", because the whole numbers include 0, and
"buying" 0 pieces of fruit would not by considered "buying". So
we rule out "Whole".

That only leaves "natural" numbers, which are 1, 2, 3, 4, ...
You can only buy natural numbers of pieces of fruit. That's it,
"Natural"!

Edwin