  We report the discovery by the WASP transit survey of three new hot Jupiters,
WASP-68 b, WASP-73 b and WASP-88 b. WASP-68 b has a mass of 0.95+-0.03 M_Jup, a
radius of 1.24-0.06+0.10 R_Jup, and orbits a V=10.7 G0-type star (1.24+-0.03
M_sun, 1.69-0.06+0.11 R_sun, T_eff=5911+-60 K) with a period of
5.084298+-0.000015 days. Its size is typical of hot Jupiters with similar
masses. WASP-73 b is significantly more massive (1.88-0.06+0.07 M_Jup) and
slightly larger (1.16-0.08+0.12 R_Jup) than Jupiter. It orbits a V=10.5 F9-type
star (1.34-0.04+0.05 M_sun, 2.07-0.08+0.19 R_sun, T_eff=6036+-120 K) every
4.08722+-0.00022 days. Despite its high irradiation (2.3 10^9 erg s^-1 cm^-2),
WASP-73 b has a high mean density (1.20-0.30+0.26 \rho_Jup) that suggests an
enrichment of the planet in heavy elements. WASP-88 b is a 0.56+-0.08 M_Jup
planet orbiting a V=11.4 F6-type star (1.45+-0.05 M_sun, 2.08-0.06+0.12 R_sun,
T_eff=6431+-130 K) with a period of 4.954000+-0.000019 days. With a radius of
1.70-0.07+0.13 R_Jup, it joins the handful of planets with super-inflated
radii. The ranges of ages we determine through stellar evolution modeling are
4.2-8.3 Gyr for WASP-68, 2.7-6.4 Gyr for WASP-73 and 1.8-5.3 Gyr for WASP-88.
WASP-73 appears to be a significantly evolved star, close to or already in the
subgiant phase. WASP-68 and WASP-88 are less evolved, although in an advanced
stage of core H-burning.
