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Finding the Fourth Proportional to 840.08, 1,258.70 and 510.81

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Solution

The fourth proportional to 840.08, 1,258.70 and 510.81 is: 765.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    840.08 : 1,258.70 = 510.81 : x
  2. Step 2: Convert to fraction form
    840.08/1,258.70 = 510.81/x
  3. Step 3: Cross multiply
    840.08x = 1,258.70 × 510.81
  4. Step 4: Simplify right side
    840.08x = 642,953.99
  5. Step 5: Solve for x
    x = 642,953.99/840.08
  6. Step 6: Final answer
    x = 765.35

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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.