Finding the Fourth Proportional to 90.78, 125.28 and 51.99
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Solution
The fourth proportional to 90.78, 125.28 and 51.99 is: 71.75
Step by Step Solution
- Step 1: Write the proportion equation
90.78 : 125.28 = 51.99 : x - Step 2: Convert to fraction form
90.78/125.28 = 51.99/x - Step 3: Cross multiply
90.78x = 125.28 × 51.99 - Step 4: Simplify right side
90.78x = 6,513.31 - Step 5: Solve for x
x = 6,513.31/90.78 - Step 6: Final answer
x = 71.75
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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.