The value of the cumulative standardized normal distribution at 1.5x is 0.9332. the value of x is

Use the table of standardized normal cumulative function.

Look up the corresponding x' for the value z=0.9332: I found x'=0.8232 (approximately).

We know that x'=1.5x, so x = 0.8232/1.5 = 0.5488