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Finding the Fourth Proportional to 521.38, 719.51 and 288.51

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Solution

The fourth proportional to 521.38, 719.51 and 288.51 is: 398.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.38 : 719.51 = 288.51 : x
  2. Step 2: Convert to fraction form
    521.38/719.51 = 288.51/x
  3. Step 3: Cross multiply
    521.38x = 719.51 × 288.51
  4. Step 4: Simplify right side
    521.38x = 207,585.83
  5. Step 5: Solve for x
    x = 207,585.83/521.38
  6. Step 6: Final answer
    x = 398.15

Related Problems

Find fourth proportional to 260.69, 359.76 and 144.26
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Double scale
Find fourth proportional to 522.38, 720.89 and 289.51
Similar ratio
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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.