Finding the Fourth Proportional to 311.81, 430.40 and 201.40
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Solution
The fourth proportional to 311.81, 430.40 and 201.40 is: 278.00
Step by Step Solution
- Step 1: Write the proportion equation
311.81 : 430.40 = 201.40 : x - Step 2: Convert to fraction form
311.81/430.40 = 201.40/x - Step 3: Cross multiply
311.81x = 430.40 × 201.40 - Step 4: Simplify right side
311.81x = 86,681.99 - Step 5: Solve for x
x = 86,681.99/311.81 - Step 6: Final answer
x = 278.00
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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.