Finding the Fourth Proportional to 420.60, 580.08 and 289.68
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Solution
The fourth proportional to 420.60, 580.08 and 289.68 is: 399.52
Step by Step Solution
- Step 1: Write the proportion equation
420.60 : 580.08 = 289.68 : x - Step 2: Convert to fraction form
420.60/580.08 = 289.68/x - Step 3: Cross multiply
420.60x = 580.08 × 289.68 - Step 4: Simplify right side
420.60x = 168,037.57 - Step 5: Solve for x
x = 168,037.57/420.60 - Step 6: Final answer
x = 399.52
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These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.