3rd Class Computers Science History of Computer First Calculating Device - The Abacus

       First Calculating Device - The Abacus

It was the first calculating device which was invented by the Chinese. It is also called a counting frame and is a calculating tool used primarily in parts of Asia for performing arithmetic processes. The abacus is a manual device. It is typically constructed of various types of hardwoods and comes in varying sizes. The frame of the abacus has a series of vertical rods on which a number of wooden beads are allowed to slide freely. A horizontal beam separates the frame into two sections, known as the upper deck and the lower deck. It is used to count, add and subtract by moving the beads up and down. These beads are marked as unit, tens and hundreds and so on from top to bottom. The beads are moved according to set rules in order to solve problems of calculation. A skilled abacus operator can do addition and subtraction work with the same speed as a modern calculator.                

 The frame of the abacus consists of series of vertical rods on which number of wooden beads are allowed to ____ freely.

(A) Roll                                                                

(B) Attach

(C) Slide    

(D) Slip

(E) None of these  

Answer: (C)

Explanation

Correct Option:

(C) Slide is the correct option.

Incorrect Options:

(A) Roll: is not used. Therefore, option (A) is Incorrect.

(B) Attach: is not used. Therefore, option (B) is Incorrect.

(D) Slip: is not used. Therefore, option (D) is Incorrect.

(E) Option (E) is Incorrect.    

 Abacus is used for counting, adding and subtracting. By moving which one of the following things in abacus you can do the calculation?

(A) Balls            

(B) Beans

(C) Beads    

(D) All of these

(E) None of these  

Answer: (C)

Explanation

Correct of Option:  

(C) By moving beads you can do the calculation

Incorrect Options:  

(A) Balls: are not used for counting in abacus. That's why option (A) is Incorrect.                                          

(B) Beans: are not used for counting in abacus. That's why option (B) is Incorrect.

(D) Option (D) is Incorrect. (E) Option (E) is Incorrect.