English

In how many ways can this diagram be coloured subject to the following two conditions? (i) Each of the smaller triangle is to be painted with one of three colours: red, blue or green.(ii) No

Advertisements
Advertisements

Question

In how many ways can this diagram be coloured subject to the following two conditions?
(i) Each of the smaller triangle is to be painted with one of three colours: red, blue or green.
(ii) No two adjacent regions have the same colour.

Sum
Advertisements

Solution

These conditions are satisfied exactly when we do as follows:

First paint the central triangle in any one of the three colours.

Next paint the remaining 3 triangles, with any one of the remaining two colours.

By the fundamental principle of counting

This can be done in 3 × 2 × 2 × 2 = 24 ways.

shaalaa.com
  Is there an error in this question or solution?
Chapter 7: Permutations and Combinations - Solved Examples [Page 116]

APPEARS IN

NCERT Exemplar Mathematics Exemplar [English] Class 11
Chapter 7 Permutations and Combinations
Solved Examples | Q 3 | Page 116

Video TutorialsVIEW ALL [1]

RELATED QUESTIONS

How many 3-digit numbers can be formed from the digits 1, 2, 3, 4 and 5 assuming that repetition of the digits is not allowed?


How many 3-digit even numbers can be formed from the digits 1, 2, 3, 4, 5, 6 if the digits can be repeated?


How many 4-letter code can be formed using the first 10 letters of the English alphabet, if no letter can be repeated?


Given 5 flags of different colours, how many different signals can be generated if each signal requires the use of 2 flags, one below the other?


A Signal is generated from 2 flags by putting one flag above the other. If 4 flags of different colours are available, how many different signals can be generated?


How many two-letter words can be formed using letters from the word SPACE, when repetition of letters is not allowed?


How many numbers between 100 and 1000 have the digit 7 exactly once?


How many two letter words can be formed using letters from the word SPACE, when repetition of letters is not allowed?


How many three-digit numbers can be formed from the digits 0, 1, 3, 5, 6 if repetitions of digits are allowed?


How many three-digit numbers can be formed from the digits 0, 1, 3, 5, 6 if repetitions of digits are not allowed?


How many three-digit numbers can be formed using the digits 2, 3, 4, 5, 6 if digits can be repeated?


A school has three gates and four staircases from the first floor to the second floor. How many ways does a student have to go from outside the school to his classroom on the second floor?


How many five-digit numbers formed using the digit 0, 1, 2, 3, 4, 5 are divisible by 5 if digits are not repeated?


In how many ways 5 persons can be seated in a row?


How many three-digit numbers are there with 3 in the unit place?
with repetition


How many three-digit numbers are there with 3 in the unit place? 
without repetition


How many numbers are there between 100 and 500 with the digits 0, 1, 2, 3, 4, 5? if the repetition of digits is not allowed


Count the numbers between 999 and 10000 subject to the condition that there are no restriction


Count the numbers between 999 and 10000 subject to the condition that there are at least one of the digits is repeated


How many three-digit numbers, which are divisible by 5, can be formed using the digits 0, 1, 2, 3, 4, 5 if repetition of digits are allowed?


In how many ways 10 pigeons can be placed in 3 different pigeon holes?


Find the number of ways of distributing 12 distinct prizes to 10 students?


Find the value of 6!


Find the value of 3! × 2!


Find the value of `(("n" + 3)!)/(("n" + 1)!)`


Find the value of n if `1/(8!) + 1/(9!) = "n"/(10!)`


Choose the correct alternative:
The number of five digit telephone numbers having at least one of their digits repeated i


In a class, there are 27 boys and 14 girls. The teacher wants to select 1 boy and 1 girl to represent the class for a function. In how many ways can the teacher make this selection?


How many numbers are there between 99 and 1000 having atleast one of their digits 7?


Out of 18 points in a plane, no three are in the same line except five points which are collinear. Find the number of lines that can be formed joining the point


The number of six-digit numbers, all digits of which are odd is ______.


Three letters can be posted in five letterboxes in 35 ways.


In a steamer there are stalls for 12 animals, and there are horses, cows and calves (not less than 12 each) ready to be shipped. They can be loaded in 312 ways.


The number of all four digit numbers which begin with 4 and end with either zero or five is ______.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×