Finding the Fourth Proportional to 420.40, 630.60 and 214.68
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Solution
The fourth proportional to 420.40, 630.60 and 214.68 is: 322.02
Step by Step Solution
- Step 1: Write the proportion equation
420.40 : 630.60 = 214.68 : x - Step 2: Convert to fraction form
420.40/630.60 = 214.68/x - Step 3: Cross multiply
420.40x = 630.60 × 214.68 - Step 4: Simplify right side
420.40x = 135,377.21 - Step 5: Solve for x
x = 135,377.21/420.40 - Step 6: Final answer
x = 322.02
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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.