Finding the Fourth Proportional to 391.19, 539.38 and 320.99
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Solution
The fourth proportional to 391.19, 539.38 and 320.99 is: 442.59
Step by Step Solution
- Step 1: Write the proportion equation
391.19 : 539.38 = 320.99 : x - Step 2: Convert to fraction form
391.19/539.38 = 320.99/x - Step 3: Cross multiply
391.19x = 539.38 × 320.99 - Step 4: Simplify right side
391.19x = 173,135.59 - Step 5: Solve for x
x = 173,135.59/391.19 - Step 6: Final answer
x = 442.59
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Why These Related Problems?
These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.