Finding the Fourth Proportional to 390.21, 584.22 and 252.91
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Solution
The fourth proportional to 390.21, 584.22 and 252.91 is: 378.66
Step by Step Solution
- Step 1: Write the proportion equation
390.21 : 584.22 = 252.91 : x - Step 2: Convert to fraction form
390.21/584.22 = 252.91/x - Step 3: Cross multiply
390.21x = 584.22 × 252.91 - Step 4: Simplify right side
390.21x = 147,755.08 - Step 5: Solve for x
x = 147,755.08/390.21 - Step 6: Final answer
x = 378.66
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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.