Given the task definition and input, reply with output. In this task, you need to answer the given multiple-choice question on the general math. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.

Problem: a group of 7 teenagers recently visited the japanese restaurant . the total bill for the meal , including 20 % gratuity , came to $ 840 . on average , how much did the meal of each individual cost before gratuity ?
Options: a ) $ 160 , b ) $ 96 , c ) $ 90 , d ) $ 10 , e ) $ 55
d