What is the sum of the first 10 terms of the arithmetic sequence ?
Answer and explanation
Correct answer: B. , from
- Step 1: The difference is 3, so . Step 2. . **Answer: . Why not the others:** 310 forgets to halve, 290 uses only the last term, and 150 uses a wrong average.
Practise more Algebra, Functions, Geometry, Combinatorics and Probability.
Free questions with an explanation for every one, and full timed Érettségi (Matura Hungary) mock tests.