Home / 949.28-1,308.84-687.20

Finding the Fourth Proportional to 949.28, 1,308.84 and 687.20

Calculator

Solution

The fourth proportional to 949.28, 1,308.84 and 687.20 is: 947.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    949.28 : 1,308.84 = 687.20 : x
  2. Step 2: Convert to fraction form
    949.28/1,308.84 = 687.20/x
  3. Step 3: Cross multiply
    949.28x = 1,308.84 × 687.20
  4. Step 4: Simplify right side
    949.28x = 899,434.85
  5. Step 5: Solve for x
    x = 899,434.85/949.28
  6. Step 6: Final answer
    x = 947.49

Related Problems

Find fourth proportional to 474.64, 654.42 and 343.60
Half scale
Find fourth proportional to 1,898.56, 2,617.68 and 1,374.40
Double scale
Find fourth proportional to 950.28, 1,310.22 and 688.20
Similar ratio
Find fourth proportional to 1,423.92, 1,963.26 and 1,030.80
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.