Finding the Fourth Proportional to 420.68, 580.21 and 315.80
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Solution
The fourth proportional to 420.68, 580.21 and 315.80 is: 435.55
Step by Step Solution
- Step 1: Write the proportion equation
420.68 : 580.21 = 315.80 : x - Step 2: Convert to fraction form
420.68/580.21 = 315.80/x - Step 3: Cross multiply
420.68x = 580.21 × 315.80 - Step 4: Simplify right side
420.68x = 183,226.63 - Step 5: Solve for x
x = 183,226.63/420.68 - Step 6: Final answer
x = 435.55
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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.