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Finding the Fourth Proportional to 783.38, 1,080.61 and 499.28

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Solution

The fourth proportional to 783.38, 1,080.61 and 499.28 is: 688.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    783.38 : 1,080.61 = 499.28 : x
  2. Step 2: Convert to fraction form
    783.38/1,080.61 = 499.28/x
  3. Step 3: Cross multiply
    783.38x = 1,080.61 × 499.28
  4. Step 4: Simplify right side
    783.38x = 539,526.96
  5. Step 5: Solve for x
    x = 539,526.96/783.38
  6. Step 6: Final answer
    x = 688.72

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Double scale
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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.