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Finding the Fourth Proportional to 520.10, 783.72 and 430.79

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Solution

The fourth proportional to 520.10, 783.72 and 430.79 is: 649.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.10 : 783.72 = 430.79 : x
  2. Step 2: Convert to fraction form
    520.10/783.72 = 430.79/x
  3. Step 3: Cross multiply
    520.10x = 783.72 × 430.79
  4. Step 4: Simplify right side
    520.10x = 337,618.74
  5. Step 5: Solve for x
    x = 337,618.74/520.10
  6. Step 6: Final answer
    x = 649.14

Related Problems

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Double scale
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Similar ratio
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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.