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Joan of Arc lead the French.
Joan is 32. Jane is 28. Jean is 16.
Answer: (1) Jean + 12 = Jane
(2) Joan = 2Jean
(3) Joan = Jane + 4 Combine (2) and (3):
2Jean = Jane + 4 Substitute for Jane from (1):
2Jean = (Jean + 12) + 4
Jean = 16
Then:
Jane = 28 (from 1)
Joan = 32 (from 2)
This is the real name of Joan Jett, the oe that is on her birth certificate.
Let Joan's age be x and her sister's be y
Then: x+y=27 and y=x-3
subsitute gives
2x-3=27
2x=30
x=15 (Joan is 15)
Subsitute back
15+y=27
y=12 (sister is 12)
Soprano Joan Sutherland was born in Sydney Australia on Nov 7th 1926