Home / 304.71-420.64-289.68

Finding the Fourth Proportional to 304.71, 420.64 and 289.68

Calculator

Solution

The fourth proportional to 304.71, 420.64 and 289.68 is: 399.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    304.71 : 420.64 = 289.68 : x
  2. Step 2: Convert to fraction form
    304.71/420.64 = 289.68/x
  3. Step 3: Cross multiply
    304.71x = 420.64 × 289.68
  4. Step 4: Simplify right side
    304.71x = 121,850.32
  5. Step 5: Solve for x
    x = 121,850.32/304.71
  6. Step 6: Final answer
    x = 399.89

Related Problems

Find fourth proportional to 152.36, 210.32 and 144.84
Half scale
Find fourth proportional to 609.42, 841.29 and 579.35
Double scale
Find fourth proportional to 305.71, 422.02 and 290.68
Similar ratio
Find fourth proportional to 457.07, 630.96 and 434.51
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.