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Finding the Fourth Proportional to 645.50, 890.78 and 350.77

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Solution

The fourth proportional to 645.50, 890.78 and 350.77 is: 484.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.50 : 890.78 = 350.77 : x
  2. Step 2: Convert to fraction form
    645.50/890.78 = 350.77/x
  3. Step 3: Cross multiply
    645.50x = 890.78 × 350.77
  4. Step 4: Simplify right side
    645.50x = 312,457.55
  5. Step 5: Solve for x
    x = 312,457.55/645.50
  6. Step 6: Final answer
    x = 484.05

Related Problems

Find fourth proportional to 322.75, 445.39 and 175.38
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Double scale
Find fourth proportional to 646.50, 892.16 and 351.77
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.