Home / 874.40-1,311.60-289.40

Finding the Fourth Proportional to 874.40, 1,311.60 and 289.40

Calculator

Solution

The fourth proportional to 874.40, 1,311.60 and 289.40 is: 434.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    874.40 : 1,311.60 = 289.40 : x
  2. Step 2: Convert to fraction form
    874.40/1,311.60 = 289.40/x
  3. Step 3: Cross multiply
    874.40x = 1,311.60 × 289.40
  4. Step 4: Simplify right side
    874.40x = 379,577.04
  5. Step 5: Solve for x
    x = 379,577.04/874.40
  6. Step 6: Final answer
    x = 434.10

Related Problems

Find fourth proportional to 437.20, 655.80 and 144.70
Half scale
Find fourth proportional to 1,748.80, 2,623.20 and 578.80
Double scale
Find fourth proportional to 875.40, 1,313.10 and 290.40
Similar ratio
Find fourth proportional to 1,311.60, 1,967.40 and 434.10
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.