Finding the Fourth Proportional to 423.70, 643.70 and 423.70
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Solution
The fourth proportional to 423.70, 643.70 and 423.70 is: 643.70
Step by Step Solution
- Step 1: Write the proportion equation
423.70 : 643.70 = 423.70 : x - Step 2: Convert to fraction form
423.70/643.70 = 423.70/x - Step 3: Cross multiply
423.70x = 643.70 × 423.70 - Step 4: Simplify right side
423.70x = 272,735.69 - Step 5: Solve for x
x = 272,735.69/423.70 - Step 6: Final answer
x = 643.70
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Why These Related Problems?
These problems maintain the same ratio (1.52) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.