Step-by-step explanation:
1. **Calculate the number of red balloons:**
- 20% of the balloons are red.
- Number of red balloons = 20% of 140 = \( \frac{20}{100} \times 140 = 28 \).
2. **Calculate the number of yellow balloons:**
- \(\frac{2}{7}\) of the balloons are yellow.
- Number of yellow balloons = \(\frac{2}{7} \times 140 = 40\).
3. **Calculate the total number of red and yellow balloons:**
- Total red and yellow balloons = 28 (red) + 40 (yellow) = 68.
4. **Calculate the number of blue balloons:**
- Total balloons = 140.
- Number of blue balloons = Total balloons - Red balloons - Yellow balloons = 140 - 68 = 72.
5. **Find the ratio of blue balloons to green balloons:**
- The ratio of blue to green balloons is 5:4.
6. **Set up the ratio equation:**
- Let the number of green balloons be \( g \).
- According to the ratio, \( \frac{5}{4} = \frac{72}{g} \).
7. **Solve for \( g \):**
- Cross-multiply to solve the ratio:
\[
5g = 4 \times 72
\]
\[
5g = 288
\]
\[
g = \frac{288}{5} = 57.6
\]
therefore Green balloons=58
