Finding the Third Proportional to 420 and 558
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Solution
The third proportional to 420 and 558 is: 741.34
Step by Step Solution
- Step 1: Write the proportion equation
420 : 558 = 558 : x - Step 2: Convert to fraction form
420/558 = 558/x - Step 3: Cross multiply
420x = 558 × 558 - Step 4: Simplify right side
420x = 311,364 - Step 5: Solve for x
x = 311,364/420 - Step 6: Final answer
x = 741.34
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Why These Related Problems?
These problems maintain the same ratio (1.33) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.