Home / 549.60-823.94-428.40

Finding the Fourth Proportional to 549.60, 823.94 and 428.40

Calculator

Solution

The fourth proportional to 549.60, 823.94 and 428.40 is: 642.24

Step by Step Solution

  1. Step 1: Write the proportion equation
    549.60 : 823.94 = 428.40 : x
  2. Step 2: Convert to fraction form
    549.60/823.94 = 428.40/x
  3. Step 3: Cross multiply
    549.60x = 823.94 × 428.40
  4. Step 4: Simplify right side
    549.60x = 352,975.90
  5. Step 5: Solve for x
    x = 352,975.90/549.60
  6. Step 6: Final answer
    x = 642.24

Related Problems

Find fourth proportional to 274.80, 411.97 and 214.20
Half scale
Find fourth proportional to 1,099.20, 1,647.88 and 856.80
Double scale
Find fourth proportional to 550.60, 825.44 and 429.40
Similar ratio
Find fourth proportional to 824.40, 1,235.91 and 642.60
1.5x scale

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.