Final answer:
The A319/A320 aircraft have their fuel tanks primarily located in the wings, with an additional one in the fuselage under the cabin for extra capacity.
Step-by-step explanation:
The fuel tanks for A319/A320 aircraft are primarily located in the wings. More specifically, each wing houses one integral fuel tank, which is an integral part of the wing structure and effectively uses the wing to store fuel. A smaller 'Center Wing Tank' is also present, which is located in the fuselage beneath the passenger cabin but is only used when necessary for extra capacity.
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