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Finding the Fourth Proportional to 840.83, 1,261.58 and 430.07

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Solution

The fourth proportional to 840.83, 1,261.58 and 430.07 is: 645.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    840.83 : 1,261.58 = 430.07 : x
  2. Step 2: Convert to fraction form
    840.83/1,261.58 = 430.07/x
  3. Step 3: Cross multiply
    840.83x = 1,261.58 × 430.07
  4. Step 4: Simplify right side
    840.83x = 542,567.71
  5. Step 5: Solve for x
    x = 542,567.71/840.83
  6. Step 6: Final answer
    x = 645.28

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1.5x scale

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.