Crack the case with George Cornelius Factor in this entertaining math adventure that introduces simplified and reduced fractions with equal parts intrigue and humor.
When a valuable fraction goes missing, George Cornelius Factor (a.k.a. GCF) vows to track it down. Knowing that the villainous Dr. Brok likes to disguise his ill-gotten fractions, GCF invents a Reducer—half ray gun, half calculator— that strips away the disguise, reducing the fraction to its lowest common denominator and revealing its true form. With the Reducer in hand, George seeks out Dr. Brok in hopes of retrieving the missing fraction.
Back matter includes more detail on simplifying, or reducing, fractions.
Einhorn, who addressed probability in A Very Improbable Story, explains simplifying fractions in this whimsical, if sometimes convoluted addition to the Charlesbridge Math Adventures series. The dorkily dapper narrator, a sort of fractions-loving cousin to Richie Rich, explains that he's been collecting fractions represented by pie graphs mounted on pedestals "for exactly 2/3 of my life." When a 5/9 comes up for auction, he bids "1/2 of a million dollars," but a competing bidder steals the object when the lights go out during the auction. George uses a whisk and computer parts to make a Reducer, a device that is "1/2 ray gun and 1/2 calculator" and can reduce a fraction to its lowest form, thereby removing its "disguise." The boy visits the thief's castle and zaps his collection of fractions in hopes of finding one that reduces to 5/9. Featuring several characters reminiscent of Ronald Searle's caricatures, Clark's (Higgins Hole) ink-and-watercolor cartoons build on the story's humor, and Einhorn works hard to give the story a sense of drama, but wordy explanations of reducing sap some of the momentum. Ages 7 10.