54
the logic is from the series 11,15,19,23
for the first row add 11 to the last number and add the result to first number and this result is multiplied by second number
for the first row add 15 to the last number and add the result to first number and this result is multiplied by second number
for the first row add 19 to the last number and add the result to first number and this result is multiplied by second number
for the first row add 23 to the last number and add the result to first number and this result is multiplied by second number