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Finding the Fourth Proportional to 491.60, 678.52 and 380.76

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Solution

The fourth proportional to 491.60, 678.52 and 380.76 is: 525.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    491.60 : 678.52 = 380.76 : x
  2. Step 2: Convert to fraction form
    491.60/678.52 = 380.76/x
  3. Step 3: Cross multiply
    491.60x = 678.52 × 380.76
  4. Step 4: Simplify right side
    491.60x = 258,353.28
  5. Step 5: Solve for x
    x = 258,353.28/491.60
  6. Step 6: Final answer
    x = 525.54

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Find fourth proportional to 245.80, 339.26 and 190.38
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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.