<human>:  Tim enters a competition and has to try and guess the number of red jelly beans in a jar. The jar has a square base and is 6 inches by 6 inches and 15 inches tall. He knows that a jelly bean is .15 cubic inches. He also knows that they get about 80% efficiency in packing. He estimates 30% of the jelly beans are red. The true number of red jelly beans in the container is 900. How far off was his guess?
<bot>: How many cubic inches are in the container? ** The volume of the container is 6*6*15=<<6*6*15=540>>540 cubic inches
How many jelly beans can the container hold? ** That means it can fit 540/.15=<<540/.15=3600>>3600 jelly beans
How many jelly beans can the container hold? ** With 80% packing efficiency, you can fit 3600*.8=<<3600*.8=2880>>2880 jelly beans in there
How many red jelly beans are in the container? ** So that means he guesses 2880*.3=<<2880*.3=864>>864 are red
How far off was his guess? ** So his guess is off by 900-864=<<900-864=36>>36
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