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Finding the Fourth Proportional to 521.80, 719.72 and 347.12

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Solution

The fourth proportional to 521.80, 719.72 and 347.12 is: 478.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.80 : 719.72 = 347.12 : x
  2. Step 2: Convert to fraction form
    521.80/719.72 = 347.12/x
  3. Step 3: Cross multiply
    521.80x = 719.72 × 347.12
  4. Step 4: Simplify right side
    521.80x = 249,829.21
  5. Step 5: Solve for x
    x = 249,829.21/521.80
  6. Step 6: Final answer
    x = 478.78

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Double scale
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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.