SSC CPO practice question
Find the value of 1³ + 2³ + 3³ + … + 30³.
From a SSC CPO Quantitative Aptitude practice set · Quantitative Aptitude
Tap an option to check your answer.
Show answer and explanation
Correct answer: (D) 216225
Σn³ = [n(n + 1)/2]² = [30 × 31/2]² = 465² = 216225. (Note Σn³ equals the square of Σn.)
हिंदी में प्रश्न
1³ + 2³ + 3³ + … + 30³ का मान ज्ञात कीजिए।
उत्तर जाँचने के लिए किसी विकल्प पर टैप करें।
उत्तर और व्याख्या देखें
सही उत्तर: (D) 216225
Σn³ = [n(n + 1)/2]² = [30 × 31/2]² = 465² = 216225। (ध्यान दें Σn³, Σn के वर्ग के बराबर है।)
More solved Quantitative Aptitude questions
- A is thrice as efficient as B and can complete a work 40 days before B. In how many days can A alone complete the work?
- The average of 4 numbers is 71. If 3 of the numbers are 16, 85, 14, find the remaining number.
- Find the LCM of 16, 20, 30 and 54.
- The temperatures (in °C) recorded in 5 cities on a winter day — four of the five values are 11, 15, 19, 23, and it is known that this…
- The true discount on a certain sum due in 1 years at 15% per annum is Rs. 175. Find the banker's gain, using BG = (TDxRxT)/100.
- Find the missing term in the series: 169, 196, ?, 256, 289