Nakul jha
  • 3

A box contains 90 discs which are numbered from 1 to 90. If one disc is drawn at random from the box, find the probability that it bears (i) a two-digit number (ii) a perfect square number (iii) a number divisible by 5.

  • 3

NCERT Solutions for Class 10 Maths Chapter 15
Important NCERT Questions
PROBABILITY
NCERT Books for Session 2022-2023
CBSE Board and UP Board Others state Board
EXERCISE 9.1
Page No:309
Questions No:18

Share

2 Answers

  1. Total number of discs = 90
    (i) Total number of two-digit numbers between 1 and 90 81
    P (getting a two-digit number) = 81/90 = 9/10
    (ii) Perfect squares between 1 and 90 are 1,4,9, 16, 25, 36, 49, 64, and 81.
    Therefore, total number of perfect squares between 1 and 90 is 9.
    P (getting a perfect square) = 9/90 = 1/10
    (iii) Numbers that are between 1 and 90 and divisible by 5 are 5, 10, 15, 20, 25, 30, 35, 40, 45, 50 55, 60, 65, 70, 75, 80, 85, and 90.
    Therefore, total numbers divisible by 5 = 18
    Probability of getting a number divisible by 5 = 18/90 = 1/5

    • 1
  2. Get Hindi Medium and English Medium NCERT Solution for Class 10 Maths to download.
    Please follow the link to visit website for first and second term exams solutions.
    https://www.tiwariacademy.com/ncert-solutions/class-10/maths/chapter-15/

    • 1
Leave an answer

Leave an answer

Browse