\(\frac{2}{3}A=\frac{2}{3}.\left(\frac{3}{5.7}+\frac{3}{7.9}+...+\frac{3}{59.61}\right)\)
\(\frac{2}{3}A=\frac{2.3}{3.5.7}+\frac{2.3}{3.7.9}+...+\frac{2.3}{3.59.61}\)
\(\frac{2}{3}A=\frac{2}{5.7}+\frac{2}{7.9}+...+\frac{2}{59.61}\)
\(\frac{2}{3}A=\frac{1}{5}-\frac{1}{7}+\frac{1}{7}-\frac{1}{9}+...+\frac{1}{59}-\frac{1}{61}\)
\(\frac{2}{3}A=\frac{1}{5}-\frac{1}{61}\)
\(\frac{2}{3}A=\frac{56}{305}\)
\(A=\frac{56}{305}.\frac{3}{2}\)
\(A=\frac{84}{305}\)
\(A=\frac{3}{5.7}+\frac{3}{7.9}+...+\frac{3}{59.61}\)
\(A=\frac{1}{5}-\frac{1}{7}+\frac{1}{7}-\frac{1}{9}+...+\frac{3}{59.61}\)
\(A=\frac{1}{5}-\frac{1}{61}\)
\(A=\frac{56}{305}\)
A=3/2 . (2/5.7 + 2/7.9 +...+2/59.61)
A=3/2 . (1/5-1/7+1/7-1/9+...+1/59-1/61)
A=3/2 . (1/5-1/61)
A=3/2 . 56/305
A=84/305
A=3/2 . (2/5.7 + 2/7.9 +...+2/59.61)
A=3/2 . (1/5 -1/7 + 1/7 - 1/9 +...+ 1/59 - 1/61)
A=3/2 . (1/5 - 1/61)
A=3/2 . 56/305
A=84/305
\(A=\frac{3}{5\cdot7}+\frac{3}{7\cdot9}+....+\frac{3}{59\cdot61}\)
\(\frac{2}{3}A=\frac{2}{5\cdot7}+\frac{2}{7\cdot9}+....+\frac{2}{59\cdot61}\)
\(\frac{2}{3}A=\frac{1}{5}-\frac{1}{7}+\frac{1}{7}-\frac{1}{9}+....+\frac{1}{59}-\frac{1}{61}\)
\(\frac{2}{3}A=\frac{1}{5}-\frac{1}{61}=\frac{56}{305}\)
\(A=\frac{56}{305}:\frac{2}{3}\)
56/305