CAT Exam  >  CAT Questions  >  The number 35a246772 is in base 9. This numbe... Start Learning for Free
The number 35a246772 is in base 9. This number when written in base 10 is divisible by 8. Find the value of digit a.
    Correct answer is '4'. Can you explain this answer?
    Verified Answer
    The number 35a246772 is in base 9. This number when written in base 10...
    (35a246772)9
    = (3 x 98) + (5 x 97) + (a x 96) + ... + (2 x 90)
    = [3 x (8 + 1)8] + [5 x (8 + 1)7] + [a x (8 + 1)6] + ... + [2 x (8 + 1)6]
    When the above expression is expanded, only the last term of each binomial expression is not divisible by 8.
    Thus, the number will be divisible when sum of its digits is divisible by 8. Sum of digits = 3 + 5 + <z + 2 + 4 + 6 + 7 + 7 + 2 = 36 + a The sum will be divisible by 8 when a = 4.
    Answer: 4
    View all questions of this test
    Most Upvoted Answer
    The number 35a246772 is in base 9. This number when written in base 10...
    N is a number in base 9.Find N when n is divided by 8(in base 10)? And N can be very large.say N=32323232....50 digits
    This can be done by converting N to base 10.But time consuming.
    What will be the fastest approach given that no proof is required.Like in a rapid fire round. Just Answer.
    One solution is: In base 9,divisibility check for 8 is sum of the digits(digit sum).Digit sum of N=25(i.e from 25*3+25*2).Converting 25 to base 10 gives 23.Thus the question changes to (23*2+23*2) in base 10 i.e 115 in base 10.COnverting it back to base 9 gives 137.Now sum of digit in base 9 is 1+3+7 i.e 12.So answers is (1+2%8)=3
    Free Test
    Community Answer
    The number 35a246772 is in base 9. This number when written in base 10...
    Conversion to Base 10
    To find the value of digit a in the number 35a246772, we first need to convert the number from base 9 to base 10.

    To convert a number from base 9 to base 10, we use the following formula:

    (number in base 10) = a[n] * 9^n + a[n-1] * 9^(n-1) + ... + a[0] * 9^0

    Where n is the number of digits in the number and a[i] represents the value of the ith digit.

    Divisibility by 8
    Next, we are given that the number in base 10 is divisible by 8. To check the divisibility of a number by 8, we need to determine if the number is a multiple of 8.

    A number is divisible by 8 if the last three digits of the number form a multiple of 8. In other words, if the remainder of the division of the last three digits by 8 is zero, then the number is divisible by 8.

    Solving the Problem
    Let's start by converting the number from base 9 to base 10:

    35a246772 = 3*9^9 + 5*9^8 + a*9^7 + 2*9^6 + 4*9^5 + 6*9^4 + 7*9^3 + 7*9^2 + 2*9^1

    Since we are given that the number is divisible by 8, we can look at the last three digits (772) and check if they form a multiple of 8.

    772 = 7*9^2 + 7*9^1 + 2*9^0 = 567 + 63 + 2 = 632

    To verify if 632 is divisible by 8, we can check if the remainder of 632/8 is zero.

    632/8 = 79 remainder 0

    Therefore, the number 35a246772 is divisible by 8, and the value of digit a is 4.
    Attention CAT Students!
    To make sure you are not studying endlessly, EduRev has designed CAT study material, with Structured Courses, Videos, & Test Series. Plus get personalized analysis, doubt solving and improvement plans to achieve a great score in CAT.
    Explore Courses for CAT exam

    Top Courses for CAT

    The number 35a246772 is in base 9. This number when written in base 10 is divisible by 8. Find the value of digit a.Correct answer is '4'. Can you explain this answer?
    Question Description
    The number 35a246772 is in base 9. This number when written in base 10 is divisible by 8. Find the value of digit a.Correct answer is '4'. Can you explain this answer? for CAT 2024 is part of CAT preparation. The Question and answers have been prepared according to the CAT exam syllabus. Information about The number 35a246772 is in base 9. This number when written in base 10 is divisible by 8. Find the value of digit a.Correct answer is '4'. Can you explain this answer? covers all topics & solutions for CAT 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for The number 35a246772 is in base 9. This number when written in base 10 is divisible by 8. Find the value of digit a.Correct answer is '4'. Can you explain this answer?.
    Solutions for The number 35a246772 is in base 9. This number when written in base 10 is divisible by 8. Find the value of digit a.Correct answer is '4'. Can you explain this answer? in English & in Hindi are available as part of our courses for CAT. Download more important topics, notes, lectures and mock test series for CAT Exam by signing up for free.
    Here you can find the meaning of The number 35a246772 is in base 9. This number when written in base 10 is divisible by 8. Find the value of digit a.Correct answer is '4'. Can you explain this answer? defined & explained in the simplest way possible. Besides giving the explanation of The number 35a246772 is in base 9. This number when written in base 10 is divisible by 8. Find the value of digit a.Correct answer is '4'. Can you explain this answer?, a detailed solution for The number 35a246772 is in base 9. This number when written in base 10 is divisible by 8. Find the value of digit a.Correct answer is '4'. Can you explain this answer? has been provided alongside types of The number 35a246772 is in base 9. This number when written in base 10 is divisible by 8. Find the value of digit a.Correct answer is '4'. Can you explain this answer? theory, EduRev gives you an ample number of questions to practice The number 35a246772 is in base 9. This number when written in base 10 is divisible by 8. Find the value of digit a.Correct answer is '4'. Can you explain this answer? tests, examples and also practice CAT tests.
    Explore Courses for CAT exam

    Top Courses for CAT

    Explore Courses
    Signup for Free!
    Signup to see your scores go up within 7 days! Learn & Practice with 1000+ FREE Notes, Videos & Tests.
    10M+ students study on EduRev