Finding the Fourth Proportional to 390.67, 585.53 and 207.79
Calculator
Solution
The fourth proportional to 390.67, 585.53 and 207.79 is: 311.43
Step by Step Solution
- Step 1: Write the proportion equation
390.67 : 585.53 = 207.79 : x - Step 2: Convert to fraction form
390.67/585.53 = 207.79/x - Step 3: Cross multiply
390.67x = 585.53 × 207.79 - Step 4: Simplify right side
390.67x = 121,666.24 - Step 5: Solve for x
x = 121,666.24/390.67 - Step 6: Final answer
x = 311.43
Related Problems
Find fourth proportional to 195.34, 292.76 and 103.90
Half scale
Find fourth proportional to 781.34, 1,171.05 and 415.58
Double scale
Find fourth proportional to 391.67, 587.02 and 208.79
Similar ratio
Find fourth proportional to 586.01, 878.29 and 311.69
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.