Given a simple high-school level math question, you are required to solve it and provide the final answer. The final answer is always a single number. These questions can range from a variety of topics like simple arithmetic, solving equations, converting a quantity from one unit to another, finding remainders/GCD/LCM, finding probabilities etc. Each question has only one correct answer. This answer can be a positive or negative integer, a fraction or a decimal number. If the answer is a negative number use the hyphen (e.g. -42) symbol for the minus sign. For decimal numbers, do not add extra zeros after the decimal point. For fractional numbers, separate the numerator and denominator using a forward slash (e.g. 3/25).
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Question: Three letters picked without replacement from ttatta. Give prob of sequence att.

Answer: 1/5


Question: What is (3/2)/((-21)/(-28) - -3)?

Answer: 2/5


Question: Calculate prob of picking 2 w and 2 l when four letters picked without replacement from {w: 3, l: 4}.

Answer:
18/35