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Finding the Fourth Proportional to 510.09, 768.61 and 420.79

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Solution

The fourth proportional to 510.09, 768.61 and 420.79 is: 634.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    510.09 : 768.61 = 420.79 : x
  2. Step 2: Convert to fraction form
    510.09/768.61 = 420.79/x
  3. Step 3: Cross multiply
    510.09x = 768.61 × 420.79
  4. Step 4: Simplify right side
    510.09x = 323,423.40
  5. Step 5: Solve for x
    x = 323,423.40/510.09
  6. Step 6: Final answer
    x = 634.05

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.