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Not all calculators have a hexadecimal mode, but if yours does, you will have more letters to spell words with. You will be able to tell if your calculator has a hexadecimal mode if you see the letters A-F on the keyboard. Calculators that have hexadecimal mode include Casios and Texas Instruments. In hexadecimal mode, you will have the letters A, B, C, D, E, and F. You can also use the numbers 1 for I, 0 for O, and 5 for S.  For example, you can spell the word "see" using 5EE. Some other words you can spell include BASS, DIE, BOSS, DOE, and SEA. When you turn your calculator upside down in hexadecimal mode, you can turn b into q and d into p. Along with q and p, you can make the letters O, D, I, Z, E, h, A, S, g/q, L, B, and G from numbers. The possibilities are endless!  b=q d=p 0=O/D 1=I 2=Z 3=E 4=h/A 5=S 6=g/q 7=L 8=B 9=G/b You can also use the number 2 instead of the word "to" or "too."
Switch your calculator to hexadecimal mode. Use a combination of letters and numbers to spell words. Create even more combinations by turning your calculator upside down.