Finding the Fourth Proportional to 420.63, 631.35 and 258.63
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Solution
The fourth proportional to 420.63, 631.35 and 258.63 is: 388.19
Step by Step Solution
- Step 1: Write the proportion equation
420.63 : 631.35 = 258.63 : x - Step 2: Convert to fraction form
420.63/631.35 = 258.63/x - Step 3: Cross multiply
420.63x = 631.35 × 258.63 - Step 4: Simplify right side
420.63x = 163,286.05 - Step 5: Solve for x
x = 163,286.05/420.63 - Step 6: Final answer
x = 388.19
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These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.