Finding the Fourth Proportional to 387.18, 534.13 and 239.79
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Solution
The fourth proportional to 387.18, 534.13 and 239.79 is: 330.80
Step by Step Solution
- Step 1: Write the proportion equation
387.18 : 534.13 = 239.79 : x - Step 2: Convert to fraction form
387.18/534.13 = 239.79/x - Step 3: Cross multiply
387.18x = 534.13 × 239.79 - Step 4: Simplify right side
387.18x = 128,080.44 - Step 5: Solve for x
x = 128,080.44/387.18 - Step 6: Final answer
x = 330.80
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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.