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Finding the Fourth Proportional to 976.76, 1,347.78 and 645.32

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Solution

The fourth proportional to 976.76, 1,347.78 and 645.32 is: 890.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    976.76 : 1,347.78 = 645.32 : x
  2. Step 2: Convert to fraction form
    976.76/1,347.78 = 645.32/x
  3. Step 3: Cross multiply
    976.76x = 1,347.78 × 645.32
  4. Step 4: Simplify right side
    976.76x = 869,749.39
  5. Step 5: Solve for x
    x = 869,749.39/976.76
  6. Step 6: Final answer
    x = 890.44

Related Problems

Find fourth proportional to 488.38, 673.89 and 322.66
Half scale
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Double scale
Find fourth proportional to 977.76, 1,349.16 and 646.32
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.