Finding the Fourth Proportional to 420.99, 630.91 and 318.19
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Solution
The fourth proportional to 420.99, 630.91 and 318.19 is: 476.85
Step by Step Solution
- Step 1: Write the proportion equation
420.99 : 630.91 = 318.19 : x - Step 2: Convert to fraction form
420.99/630.91 = 318.19/x - Step 3: Cross multiply
420.99x = 630.91 × 318.19 - Step 4: Simplify right side
420.99x = 200,749.25 - Step 5: Solve for x
x = 200,749.25/420.99 - Step 6: Final answer
x = 476.85
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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.