NoMethodError when running RSpec test

I am getting the error NoMethodError when trying to use RSpec for testing the gem I created.

this is my gem: ~/project/gemz/spec/lib/checksomething.rb

    class Checkpercentage

    #1) what is  x% of y?
    def self.findAmount(rate, base)
    resultAmount = rate * base/100
    return resultAmount

    end 

    #2) x is what percentage of y?
    def self.findPercent(amount, base)
        resultPercent = amount/base * 100
        return resultPercent
    end

    #3) x is y% of what number?
    def self.findBase(amount, rate)
        resultBase = amount/rate *100
        return resultBase
    end
    end # End Module

And this is my rspec test file: ./project/gemz/spec/lib/checkpercentage_spc.rb

    require "spec_helper"
    require "checksomething"

    RSpec.describe Checkpercentage, '#intNum' do
         context "with no integer entered" do
            it "must be a number" do
                checkpercentage = Checkpercentage.new
                checkpercentage.findPercent(100, 200)
                expect(checkpercentage.intNum) > 0
            end
         end
    end

I want to test if the values enterend in the findPercentage method are > 0. However, when I run the rspec command in my terminal (rspec spec/lib/checkpercentage_spc.rb) the following error comes up:

    Failures:

      1) Checkpercentage#intNum with no integer entered must be a number
         Failure/Error: 20.times {checkpercentage.findPercent(100, 200)}
         NoMethodError:
           undefined method `findPercent' for #<Checkpercentage:0xad3de84>
         # ./spec/lib/checkpercentage_spc.rb:8:in `block (4 levels) in <top (required)>'
         # ./spec/lib/checkpercentage_spc.rb:8:in `times'
         # ./spec/lib/checkpercentage_spc.rb:8:in `block (3 levels) in <top (required)>'

    Finished in 0.00118 seconds (files took 0.66969 seconds to load)
    1 example, 1 failure

    Failed examples:

    rspec ./spec/lib/checkpercentage_spc.rb:6 # Checkpercentage#intNum with no integer entered must be a number

I'm fairly new at ruby on rails. Can anyone point me to the right direction? Any help is appreciated.