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Finding the Fourth Proportional to 653.60, 901.50 and 420.50

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Solution

The fourth proportional to 653.60, 901.50 and 420.50 is: 579.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    653.60 : 901.50 = 420.50 : x
  2. Step 2: Convert to fraction form
    653.60/901.50 = 420.50/x
  3. Step 3: Cross multiply
    653.60x = 901.50 × 420.50
  4. Step 4: Simplify right side
    653.60x = 379,080.75
  5. Step 5: Solve for x
    x = 379,080.75/653.60
  6. Step 6: Final answer
    x = 579.99

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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.