425 is decreased to 319.
"Decreased to" and "decreased by" have different meaning.
"decreased to" means that the number given after the phrase is the difference in the subtraction.
"decreased by" means that the number given after the phrase is the number deducted from the other number to get the difference.
319 is the difference. We need to get the number to be deducted from 425.
425 - x = 319
425 - 319 = x
106 = x
to check:
425 - 106 = 319
319 = 319