ACT English Practice Test 12

Puzzling Numbers

The Japanese number game Sudoku has taken the world with Q1 storm. While crossword puzzles seem to be the game of choice, they need Q2 only sit in an airport or doctor’s office in any city to see how Sudoku is slowly overtaking the popular word game.

In the most common game of Sudoku, the player is faced with a nine-by-nine space grid with a total of 81 spaces. The solution to the puzzle requires a number, one through nine, to be placed in each box. Q3 Each number must appear only once in each row and only once in each column. A Sudoku puzzle will begin with a few digits already in place. The solver’s task, is Q4 to figure out which numeral belongs in the remaining empty spaces. While being a math whiz is no requirement for this seemingly simple process, a level of logic and reasoning is Q5 necessary in order to choose the correct number for each space. As with most such activities, practice makes perfect with Sudoku. The puzzles that seem impossible at first glance eventual become Q6 more manageable.

The name Sudoku is derived from the phrase single number in the Japanese language. Nevertheless, Q7 its definition refers to the placement or allotment of a single number. This puzzle is aptly named, since Q8 the misplacement of a single number spells the beginning of an incorrect solution. For this reason, Sudoku should have been Q9 played using a pencil with a good eraser.

It is nearly impossible to discern which number Q10 the solver has placed incorrectly once an error is discovered. If you don’t have a pencil, use a pen to write the digit as a series of light dots. This way, should you make a mistake,Q11 you can retrace your steps to locate and correct the original errant placement.

There are certain strategies involved in solving a Sudoku puzzle, including the process of elimination. For example, if a row of nine spaces already has the number 4, that row cannot contain another 4. This goes for columns as well. The solver can use these clues and a bit of deduction to limit the possible combinations of numbers. By attacking the puzzle using logic, Q12 you can turn the process into an amusing challenge rather than an impossible task.

[1] The origin of Sudoku is attributed to Leonhard Euler, the Swiss mathematician who sometimes Q13 developed the game Magic Squares in 1783. [2] In fact, Euler’s game was actually based on a game derived from Chinese folklore. [3] The primary difference between Magic Squares and Sudoku is that Euler’s game has no grid dividing the puzzle and it is somewhat easier to solve, since there are multiple possibilities for a solution. [4] In true Sudoku, each puzzle has only one solution. [5] The puzzle’s difficulty varies according to the number of digits that are initially provided. [6] When faced with a puzzle with only one 3 provided, for example, you can be sure that it will be more difficult to solve than a puzzle that already has half of the numbers placed in the correct boxes. Q14

One has only to examine a local newspaper to ascertain the popularity of this addictive brain teaser. Where comics and crossword puzzles reign supreme, it is often easy to locate a grid of spaces and numbers tucked off in a corner, or even sitting boldly next to the time-honored crossword.

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