To find the total water level of the river at the end of summer, we need to add the two depths below sea level together.
- The initial water level is \(1 \frac{1}{2}\) meters below sea level, which can be converted to an improper fraction:
\[ 1 \frac{1}{2} = \frac{3}{2} \text{ meters} \]
- The additional drop in water level during the summer is \(2 \frac{1}{3}\) meters below sea level, which can also be converted to an improper fraction:
\[ 2 \frac{1}{3} = \frac{7}{3} \text{ meters} \]
- Now, we need to add these two fractions. To do this, we will first find a common denominator. The least common multiple of 2 and 3 is 6.
Convert \(\frac{3}{2}\) and \(\frac{7}{3}\) to have a denominator of 6:
\[ \frac{3}{2} = \frac{3 \times 3}{2 \times 3} = \frac{9}{6} \]
\[ \frac{7}{3} = \frac{7 \times 2}{3 \times 2} = \frac{14}{6} \]
- Now, we can add the two fractions:
\[ \frac{9}{6} + \frac{14}{6} = \frac{9 + 14}{6} = \frac{23}{6} \]
- This means the water level at the end of summer is \(\frac{23}{6}\) meters below sea level. To express this as a mixed number:
\[ \frac{23}{6} = 3 \frac{5}{6} \]
Thus, the water level at the end of summer is
\[ 3 \frac{5}{6} \text{ meters below sea level.} \]
To summarize, the final answer is:
3 5/6 meters below sea level.