Finding the Fourth Proportional to 77.15, 115.68 and 25.78
Calculator
Solution
The fourth proportional to 77.15, 115.68 and 25.78 is: 38.65
Step by Step Solution
- Step 1: Write the proportion equation
77.15 : 115.68 = 25.78 : x - Step 2: Convert to fraction form
77.15/115.68 = 25.78/x - Step 3: Cross multiply
77.15x = 115.68 × 25.78 - Step 4: Simplify right side
77.15x = 2,981.94 - Step 5: Solve for x
x = 2,981.94/77.15 - Step 6: Final answer
x = 38.65
Related Problems
Find fourth proportional to 38.57, 57.84 and 12.89
Half scale
Find fourth proportional to 154.29, 231.36 and 51.56
Double scale
Find fourth proportional to 78.15, 117.18 and 26.78
Similar ratio
Find fourth proportional to 115.72, 173.52 and 38.67
1.5x scale
Why These Related Problems?
These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.