Let x amount is invested at 16% rate, then remaining amount (91 - x) is invested in 14% rate.
Determine the intrest earned at 16% rate and at 14% rate after one year.

For 14% rate,

The sum of the intrest is equal to 13.74. So,

So $50 is invested at 16% rate.
Determine the invest amount in 14% rate.

So invest amount in 14% rate is $41.
Thus answer is,
At rate of 16%: $50
At rate of 14%: $41