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Finding the Fourth Proportional to 1,035.60, 1,429.20 and 642.75

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Solution

The fourth proportional to 1,035.60, 1,429.20 and 642.75 is: 887.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,035.60 : 1,429.20 = 642.75 : x
  2. Step 2: Convert to fraction form
    1,035.60/1,429.20 = 642.75/x
  3. Step 3: Cross multiply
    1,035.60x = 1,429.20 × 642.75
  4. Step 4: Simplify right side
    1,035.60x = 918,618.30
  5. Step 5: Solve for x
    x = 918,618.30/1,035.60
  6. Step 6: Final answer
    x = 887.04

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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.