Finding the Fourth Proportional to 420.70, 630.99 and 215.20
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Solution
The fourth proportional to 420.70, 630.99 and 215.20 is: 322.77
Step by Step Solution
- Step 1: Write the proportion equation
420.70 : 630.99 = 215.20 : x - Step 2: Convert to fraction form
420.70/630.99 = 215.20/x - Step 3: Cross multiply
420.70x = 630.99 × 215.20 - Step 4: Simplify right side
420.70x = 135,789.05 - Step 5: Solve for x
x = 135,789.05/420.70 - Step 6: Final answer
x = 322.77
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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.