Home / 446.60-669.90-421.40

Finding the Fourth Proportional to 446.60, 669.90 and 421.40

Calculator

Solution

The fourth proportional to 446.60, 669.90 and 421.40 is: 632.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    446.60 : 669.90 = 421.40 : x
  2. Step 2: Convert to fraction form
    446.60/669.90 = 421.40/x
  3. Step 3: Cross multiply
    446.60x = 669.90 × 421.40
  4. Step 4: Simplify right side
    446.60x = 282,295.86
  5. Step 5: Solve for x
    x = 282,295.86/446.60
  6. Step 6: Final answer
    x = 632.10

Related Problems

Find fourth proportional to 223.30, 334.95 and 210.70
Half scale
Find fourth proportional to 893.20, 1,339.80 and 842.80
Double scale
Find fourth proportional to 447.60, 671.40 and 422.40
Similar ratio
Find fourth proportional to 669.90, 1,004.85 and 632.10
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.