Hassan made a profit of 5% by selling an article for 6200. How much should he have sold the article to make a profit of 15%

For the rule of 78, for a 12-month period, the last term in the sequence is 12 and the series sums to 78. for an 10 month period, the last term is and the series sum is . for a 15 month period, the last term is and the series sum is . for a 20 month period, the last term is and the series sum is

Hi, can anyone show me how to do this problem? 100 points for this. in advance

What is the value of the expression i 0 × i 1 × i 2 × i 3 × i 4? 1 –1 i –i