Finding the Fourth Proportional to 428.42, 642.72 and 135.99
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Solution
The fourth proportional to 428.42, 642.72 and 135.99 is: 204.01
Step by Step Solution
- Step 1: Write the proportion equation
428.42 : 642.72 = 135.99 : x - Step 2: Convert to fraction form
428.42/642.72 = 135.99/x - Step 3: Cross multiply
428.42x = 642.72 × 135.99 - Step 4: Simplify right side
428.42x = 87,403.49 - Step 5: Solve for x
x = 87,403.49/428.42 - Step 6: Final answer
x = 204.01
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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.