(7/25+1/5) : 3/50=

To solve the expression \((\frac{7}{25} + \frac{1}{5}) : \frac{3}{50}\), we first need to simplify the addition in the parentheses.

1. Convert \(\frac{1}{5}\) to have a common denominator with \(\frac{7}{25}\): \[ \frac{1}{5} = \frac{5}{25} \]

2. Now, add the fractions: \[ \frac{7}{25} + \frac{5}{25} = \frac{12}{25} \]

Now, the expression becomes: \[ \frac{12}{25} : \frac{3}{50} \]

3. Dividing a fraction by another fraction is the same as multiplying by the reciprocal: \[ \frac{12}{25} \div \frac{3}{50} = \frac{12}{25} \times \frac{50}{3} \]

4. Multiply the fractions: \[ = \frac{12 \times 50}{25 \times 3} = \frac{600}{75} \]

5. Now, simplify \(\frac{600}{75}\): \[ \frac{600 \div 75}{75 \div 75} = \frac{8}{1} = 8 \]

Thus, the final answer is: \[ \boxed{8} \]