Finding the Fourth Proportional to 428.50, 642.75 and 135.99
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Solution
The fourth proportional to 428.50, 642.75 and 135.99 is: 203.99
Step by Step Solution
- Step 1: Write the proportion equation
428.50 : 642.75 = 135.99 : x - Step 2: Convert to fraction form
428.50/642.75 = 135.99/x - Step 3: Cross multiply
428.50x = 642.75 × 135.99 - Step 4: Simplify right side
428.50x = 87,408.27 - Step 5: Solve for x
x = 87,408.27/428.50 - Step 6: Final answer
x = 203.99
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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.