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Finding the Fourth Proportional to 653.40, 980.40 and 345.18

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Solution

The fourth proportional to 653.40, 980.40 and 345.18 is: 517.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    653.40 : 980.40 = 345.18 : x
  2. Step 2: Convert to fraction form
    653.40/980.40 = 345.18/x
  3. Step 3: Cross multiply
    653.40x = 980.40 × 345.18
  4. Step 4: Simplify right side
    653.40x = 338,414.47
  5. Step 5: Solve for x
    x = 338,414.47/653.40
  6. Step 6: Final answer
    x = 517.93

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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.