# Calculate the number 472

NUMBERMANIA: Calculate the number 472 using numbers [9, 2, 1, 8, 12, 526] and basic arithmetic operations (+, -, *, /). Each of the numbers can be used only once.Correct answers:

**1**#brainteasers #math #numbermania

Correct answers: **1**

#brainteasers #math #numbermania

## Harold Stephen BlackBorn 14 Apr 1898; died 11 Dec 1983 at age 85.American electrical engineer who discovered and developed the negative-feedback principle, in which amplification output is fed back into the input, thus producing nearly distortionless and steady amplification. In 1921, Black joined the forerunner of Bell Labs, in New York City, working on elimination of distortion. After six years of persistence, Black conceived his negative feedback amplifier in a flash commuting to work aboard the ferry. Basically, the concept involved feeding systems output back to the input as a method of system control. The principle has found widespread applications in electronics, including industrial, military, and consumer electronics, weaponry, analog computers, and such biomechanical devices as pacemakers. |

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