Finding the Fourth Proportional to 420.36, 629.70 and 201.20
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Solution
The fourth proportional to 420.36, 629.70 and 201.20 is: 301.40
Step by Step Solution
- Step 1: Write the proportion equation
420.36 : 629.70 = 201.20 : x - Step 2: Convert to fraction form
420.36/629.70 = 201.20/x - Step 3: Cross multiply
420.36x = 629.70 × 201.20 - Step 4: Simplify right side
420.36x = 126,695.64 - Step 5: Solve for x
x = 126,695.64/420.36 - Step 6: Final answer
x = 301.40
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Why These Related Problems?
These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.