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Finding the Fourth Proportional to 652.76, 900.90 and 390.80

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Solution

The fourth proportional to 652.76, 900.90 and 390.80 is: 539.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    652.76 : 900.90 = 390.80 : x
  2. Step 2: Convert to fraction form
    652.76/900.90 = 390.80/x
  3. Step 3: Cross multiply
    652.76x = 900.90 × 390.80
  4. Step 4: Simplify right side
    652.76x = 352,071.72
  5. Step 5: Solve for x
    x = 352,071.72/652.76
  6. Step 6: Final answer
    x = 539.36

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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.