There seems to be a typo. You wrote 1313, but I'm assuming you meant to say the fraction 1/3. If this assumption is correct, then continue with the rest of the solution. If the assumption is not correct, then ignore what I wrote below and please provide clarification of what the "1313" should represent. Thank you.
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B = your brother's age
S = your sister's age
Y = your age
All of these ages are current present day ages.
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"your brother is 1/3 your age" so B = (1/3)Y or B = Y/3.
"Your sister is 6 years older than your brother" so S = B+6
"Your sister is 10 years old" so S = 10.
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S = B+6
B+6 = S
B+6 = 10 ... plug in S = 10
B+6-6 = 10-6 ... subtract 6 from both sides
B = 4
Your brother is 4 years old.
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B = Y/3
Y/3 = B
Y/3 = 4 .... plug in B = 4
3(Y/3) = 3*4 ... multiply both sides by 3
Y = 12
Answer: Your age is 12 years old.
note: This answer hinges on assumption that the "1313" should be "1/3".