Use app×
Join Bloom Tuition
One on One Online Tuition
JEE MAIN 2025 Foundation Course
NEET 2025 Foundation Course
CLASS 12 FOUNDATION COURSE
CLASS 10 FOUNDATION COURSE
CLASS 9 FOUNDATION COURSE
CLASS 8 FOUNDATION COURSE
0 votes
83 views
in Probability by (51.4k points)
closed by

The probability that the sum of squares of two non-negative integers is divisible by 5 is

(a) \(\frac7{25}\)

(b) \(\frac8{25}\)

(c) \(\frac9{25}\)

(d) \(\frac2{25}\)

1 Answer

+1 vote
by (51.1k points)
selected by
 
Best answer

Correct option is (c) \(\frac9{25}\) 

Let two non-negative integers be x & y such that x = 5a + α and y = 5b + β where 0 ≤ α,β ≤ 4.

New, x+ y2 = 25(a+ b2) + 10(aα + bβ) + α2 + β2 

⇒ α2 + β2 should be divisible by 5

 \(\therefore\) (α, β) can have ordered pairs as

{(0,0), (1,2), (2,1), (1,3), (3,1), (2,4), (4,2), (3,4), (4,3)} = 9 ways

\(\therefore\) required probability is \(\frac 9{25}\).

Welcome to Sarthaks eConnect: A unique platform where students can interact with teachers/experts/students to get solutions to their queries. Students (upto class 10+2) preparing for All Government Exams, CBSE Board Exam, ICSE Board Exam, State Board Exam, JEE (Mains+Advance) and NEET can ask questions from any subject and get quick answers by subject teachers/ experts/mentors/students.

Categories

...