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Finding the Fourth Proportional to 630.76, 870.22 and 378.60

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Solution

The fourth proportional to 630.76, 870.22 and 378.60 is: 522.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.76 : 870.22 = 378.60 : x
  2. Step 2: Convert to fraction form
    630.76/870.22 = 378.60/x
  3. Step 3: Cross multiply
    630.76x = 870.22 × 378.60
  4. Step 4: Simplify right side
    630.76x = 329,462.69
  5. Step 5: Solve for x
    x = 329,462.69/630.76
  6. Step 6: Final answer
    x = 522.32

Related Problems

Find fourth proportional to 315.38, 435.11 and 189.30
Half scale
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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.