+635 Compute
\frac{1}{1 \times 4} + \frac{1}{7 \times 10} + \frac{1}{37 + 40}
+15000 \(\frac{1}{1 \cdot 4} + \frac{1}{7 \cdot 10} + \frac{1}{37 + 40}\\ =\frac{1}{1 \cdot 2^2} + \frac{1}{7 \cdot 2\cdot 5} + \frac{1}{7\cdot 11}\\ =\frac{5\cdot7\cdot 11+2\cdot 11+2^2\cdot 5}{2^2\cdot 5\cdot7\cdot 11}\\ =\frac{427}{2^2\cdot 5\cdot7\cdot 11}\\ =\frac{7\cdot 61}{2^2\cdot 5\cdot7\cdot 11}\\ \color{blue}=\frac{61}{2^2\cdot 5\cdot 11}\)
!
+57 1/4+1/70+1/77
1/70+1/77=21/770=3/110
3/110+1/4 = 61/220
correct me if i'm wrong!
