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Finding the Fourth Proportional to 840.82, 1,262.40 and 430.28

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Solution

The fourth proportional to 840.82, 1,262.40 and 430.28 is: 646.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    840.82 : 1,262.40 = 430.28 : x
  2. Step 2: Convert to fraction form
    840.82/1,262.40 = 430.28/x
  3. Step 3: Cross multiply
    840.82x = 1,262.40 × 430.28
  4. Step 4: Simplify right side
    840.82x = 543,185.47
  5. Step 5: Solve for x
    x = 543,185.47/840.82
  6. Step 6: Final answer
    x = 646.02

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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.