Tag: properties and patterns of perfect squares

Questions Related to properties and patterns of perfect squares

Multiple choice maths fun with numbers some special sequences triangular numbers properties and patterns of perfect squares

If $\displaystyle { a }^{ 2 }$ ends in 5, then $\displaystyle { a }^{ 3 }$ ends in 25.

  1. True

  2. False

  3. Ambiguous

  4. Insufficient information

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

False. 15 x 15=225 and 15 x 15 x 15=3375. so the statement $\displaystyle { a }^{ 2 }$ ends in 5, then $\displaystyle { a }^{ 3 }$ ends in 25 is not true in all cases.

Multiple choice maths fun with numbers some special sequences triangular numbers properties and patterns of perfect squares

If $\displaystyle n = 1 + x $, where $x$ is the product of four consecutive positive integers then which of the following is/are true:
A) n is odd

B) n is prime
C) n is a perfect square

  1. A and C only

  2. A and B only

  3. A only

  4. None of these

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Let us take $\displaystyle x=1\times2\times3\times4=24 $

Then $\displaystyle n=1+24=25$
i.e. an odd number and a perfect square
Again let $\displaystyle x=2\times3\times4\times5=120.$
Then, $\displaystyle n=1+120=121$
i.e. an odd number and a perfect square
$\displaystyle \therefore $ Option (A) is correct