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Finding the Fourth Proportional to 1,289.95, 1,780.17 and 730.45

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Solution

The fourth proportional to 1,289.95, 1,780.17 and 730.45 is: 1,008.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,289.95 : 1,780.17 = 730.45 : x
  2. Step 2: Convert to fraction form
    1,289.95/1,780.17 = 730.45/x
  3. Step 3: Cross multiply
    1,289.95x = 1,780.17 × 730.45
  4. Step 4: Simplify right side
    1,289.95x = 1,300,325.18
  5. Step 5: Solve for x
    x = 1,300,325.18/1,289.95
  6. Step 6: Final answer
    x = 1,008.04

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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.