मराठी

Observe the Patterns of Digits Made from Line Segments of Equal Length. You Will Find Such Segmented Digits on the Display of Electronic Watches Or Calculators. - Mathematics

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प्रश्न

Observe the patterns of digits made from line segments of equal length. You will find such segmented digits on the display of electronic watches or calculators.

If the number of digits formed is taken to be n, the number of segments required to
form n digits is given by the algebraic expression appearing on the right of each pattern.

How many segments are required to form 5, 10, 100 digits of the kind −

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उत्तर

It is given that the number of segments required to form n digits of the kind 

 

is (5n + 1)

Number of segments required to form 5 digits = (5 × 5 + 1)

= 25 + 1 = 26

Number of segments required to form 10 digits = (5 × 10 + 1)

= 50 + 1 = 51

Number of segments required to form 100 digits = (5 × 100 + 1)

= 500 + 1 = 501

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पाठ 12: Algebraic Expressions - Exercise 12.4 [पृष्ठ २४६]

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एनसीईआरटी Mathematics [English] Class 7
पाठ 12 Algebraic Expressions
Exercise 12.4 | Q 1.1 | पृष्ठ २४६

संबंधित प्रश्‍न

Observe the patterns of digits made from line segments of equal length. You will find such segmented digits on the display of electronic watches or calculators.

If the number of digits formed is taken to be n, the number of segments required to form n digits is given by the algebraic expression appearing on the right of each pattern.

How many segments are required to form 5, 10, 100 digits of the kind −


Use the given algebraic expression to complete the table of number patterns.

S. No


Expression

Terms
1st 2nd 3rd 4th 5th ... 10th ... 100th ...
1 2n - 1 1 3 5 7 9 - 19 - - -
2 3n + 2 5 8 11 14 - - - - - -
3 4n + 1 5 9 13 17 - - - - - -
4 7n + 20 27 34 41 48 - - - - - -
5 n2 + 1 2 5 10 17 - - - - 10001 -

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