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Finding the Fourth Proportional to 518.70, 715.56 and 378.75

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Solution

The fourth proportional to 518.70, 715.56 and 378.75 is: 522.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    518.70 : 715.56 = 378.75 : x
  2. Step 2: Convert to fraction form
    518.70/715.56 = 378.75/x
  3. Step 3: Cross multiply
    518.70x = 715.56 × 378.75
  4. Step 4: Simplify right side
    518.70x = 271,018.35
  5. Step 5: Solve for x
    x = 271,018.35/518.70
  6. Step 6: Final answer
    x = 522.50

Related Problems

Find fourth proportional to 259.35, 357.78 and 189.38
Half scale
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Double scale
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Similar ratio
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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.