Finding the Fourth Proportional to 420.91, 630.14 and 378.99
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Solution
The fourth proportional to 420.91, 630.14 and 378.99 is: 567.38
Step by Step Solution
- Step 1: Write the proportion equation
420.91 : 630.14 = 378.99 : x - Step 2: Convert to fraction form
420.91/630.14 = 378.99/x - Step 3: Cross multiply
420.91x = 630.14 × 378.99 - Step 4: Simplify right side
420.91x = 238,816.76 - Step 5: Solve for x
x = 238,816.76/420.91 - Step 6: Final answer
x = 567.38
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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.