यदि (1² + 2² + 3² + ......+ 20²) = 2870 हो तो (2² + 4² + 6² + ...........+ 40²) = ? - - Yadi (12 + 22 + 32 + ......+ 202) = 2870 Ho To (22 + 42 + 62 + ...........+ 402) = ? Maths in hindi, number system 5740 question answers in hindi pdf 11480 questions in hindi, Know About 2870 Maths online test Maths notes in hindi quiz book 28700