## Thursday, September 12, 2019

### Review of "Calculator Riddles," by David A. Adler

Review of

Calculator Riddles, by David A. Adler ISBN 0823411869

Five out of five stars

These riddles are based on the appearance of the characters on the readout of a digital calculator. When they are turned upside down, eight of the digits look like letters in the Latin alphabet. A zero is an O, a one is an I, a three becomes an E, a four becomes an h, a five is an S, a seven is an L, an eight is a B and a nine is a G. There are many words that can be made from these eight letters and those words are formed by the execution of a linear sequence of arithmetic operations on the calculator followed by turning it over.

A series of numbers and operations are to be entered on the calculator and they are to be executed in the sequence from left to right, independent of the usual order of operations. The riddle is to determine what the word is before carrying out the calculator operations. They are all simple riddles and the only calculator operations used are addition, subtraction, multiplication and division. Many of the exercises would make fun problems in math tests given to elementary school students. Nothing mathematically complex, just simple fun.