Finding the Fourth Proportional to 432, 648 and 420
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Solution
The fourth proportional to 432, 648 and 420 is: 630
Step by Step Solution
- Step 1: Write the proportion equation
432 : 648 = 420 : x - Step 2: Convert to fraction form
432/648 = 420/x - Step 3: Cross multiply
432x = 648 × 420 - Step 4: Simplify right side
432x = 272,160 - Step 5: Solve for x
x = 272,160/432 - Step 6: Final answer
x = 630
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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.