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Finding the Fourth Proportional to 521.63, 719.85 and 288.76

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Solution

The fourth proportional to 521.63, 719.85 and 288.76 is: 398.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.63 : 719.85 = 288.76 : x
  2. Step 2: Convert to fraction form
    521.63/719.85 = 288.76/x
  3. Step 3: Cross multiply
    521.63x = 719.85 × 288.76
  4. Step 4: Simplify right side
    521.63x = 207,860.29
  5. Step 5: Solve for x
    x = 207,860.29/521.63
  6. Step 6: Final answer
    x = 398.48

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Find fourth proportional to 260.82, 359.93 and 144.38
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Double scale
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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.