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Finding the Fourth Proportional to 630.34, 870.15 and 378.38

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Solution

The fourth proportional to 630.34, 870.15 and 378.38 is: 522.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.34 : 870.15 = 378.38 : x
  2. Step 2: Convert to fraction form
    630.34/870.15 = 378.38/x
  3. Step 3: Cross multiply
    630.34x = 870.15 × 378.38
  4. Step 4: Simplify right side
    630.34x = 329,250.95
  5. Step 5: Solve for x
    x = 329,250.95/630.34
  6. Step 6: Final answer
    x = 522.34

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Half scale
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Double scale
Find fourth proportional to 631.34, 871.53 and 379.38
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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.