What is the value of \(20^2 + 5\)?
Answer and explanation
Correct answer: 405
Apply the exponent first: \(20^2=400\). Adding 5 gives \(400+5=405\). Why other choices are wrong: 395 likely comes from mistakenly subtracting 5 (\(400-5\)); 415 would arise if 15 were added instead of 5; 420 could come from confusing the expression with \(20\times21\). Exam tip: evaluate powers before addition and double-check simple arithmetic to avoid common slip-ups.
Frequently asked questions
What is the correct answer to this question?
405
Why is this the correct answer?
Apply the exponent first: \(20^2=400\). Adding 5 gives \(400+5=405\). Why other choices are wrong: 395 likely comes from mistakenly subtracting 5 (\(400-5\)); 415 would arise if 15 were added instead of 5; 420 could come from confusing the expression with \(20\times21\). Exam tip: evaluate powers before addition and double-check simple arithmetic to avoid common slip-ups.
Which subject and chapter does this question cover?
This is a Class 9 Mathematics question. Chapter: Number Systems. Topic: Exponents.
Student feedback
Was this question useful?
👍 0 Helpful 👎 0 Not helpful
Yes 0% No 0%
0 responsesStudent Reviews
No published reviews yet.
