Finding the Fourth Proportional to 689.40, 1,034.45 and 458.45
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Solution
The fourth proportional to 689.40, 1,034.45 and 458.45 is: 687.91
Step by Step Solution
- Step 1: Write the proportion equation
689.40 : 1,034.45 = 458.45 : x - Step 2: Convert to fraction form
689.40/1,034.45 = 458.45/x - Step 3: Cross multiply
689.40x = 1,034.45 × 458.45 - Step 4: Simplify right side
689.40x = 474,243.60 - Step 5: Solve for x
x = 474,243.60/689.40 - Step 6: Final answer
x = 687.91
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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.