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Finding the Fourth Proportional to 661.60, 913.17 and 440.78

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Solution

The fourth proportional to 661.60, 913.17 and 440.78 is: 608.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    661.60 : 913.17 = 440.78 : x
  2. Step 2: Convert to fraction form
    661.60/913.17 = 440.78/x
  3. Step 3: Cross multiply
    661.60x = 913.17 × 440.78
  4. Step 4: Simplify right side
    661.60x = 402,504.16
  5. Step 5: Solve for x
    x = 402,504.16/661.60
  6. Step 6: Final answer
    x = 608.38

Related Problems

Find fourth proportional to 330.80, 456.59 and 220.39
Half scale
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Double scale
Find fourth proportional to 662.60, 914.55 and 441.78
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.