alleryIf a + 1/a = 5, then a^2 + 1/a^2 is
A25
B27
C21
D23
Answer & Solution
Correct answer: D. 23
(a + 1/a)^2 = a^2 + 2 + 1/a^2 = 25. So a^2 + 1/a^2 = 25 - 2 = 23.
Keep practising Multiplication
Browse all Multiplication questions for GRE, or explore more Quantitative Aptitude topics.
Related questions
A television costs Rs 13,000 and sales tax is charged at 12 per cent. What is the total pa72 per cent of 25 students are interested in mathematics. How many are not interested?A team won 10 matches and its win percentage was 40. How many matches did it play in all?Chameli has Rs 600 left after spending 75 per cent of her money. How much did she start wiBy what per cent is Rs 2,000 less than Rs 2,400?An article is purchased for Rs 1,239 including GST of 18 per cent. What is the price beforA hair dryer is purchased for Rs 5,400 including 8 per cent VAT. What was the price beforeArun buys skates in a sale with 20 per cent discount and pays Rs 1,600. What was the marke