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M66 and M96 in the Leo I Group are nearby spiral galaxies hosting Type IaSupernovae (SNe Ia). We estimate the distances to these galaxies from theluminosity of the tip of the red giant branch (TRGB). We obtain $VI$ photometryof resolved stars in these galaxies from $F555W$ and $F814W$ images in the {\itHubble Space Telescope} archive. From the luminosity function of these redgiants we find the TRGB $I$-band magnitude to be $I_{\rm TRGB}=26.20\pm0.03$for M66 and $26.21\pm0.03$ for M96. These values yield distance modulus$(m-M)_0=30.12\pm0.03 ({\rm random})\pm0.12 ({\rm systematic})$ for M66 and$(m-M)_0=30.15\pm0.03 ({\rm random})\pm0.12 ({\rm systematic})$ for M96. Theseresults show that they are indeed the members of the same group. With theseresults we derive absolute maximum magnitudes of two SNe (SN 1989B in M66 andSN 1998bu in M96). $V$-band magnitudes of these SNe Ia are $\sim$0.2 magfainter than SN 2011fe in M101, the nearest recent SN Ia. We also derivenear-infrared magnitudes for SN 1998bu. Optical magnitudes of three SNe Ia (SN1989B, SN 1998bu, and SN 2011fe) based on TRGB analysis yield a Hubbleconstant, $H_0=67.6\pm1.5 ({\rm random})\pm 3.7({\rm systematic})$ \kmsMpc.This value is similar to the values derived from recent WMAP9 results,$H_0=69.32\pm0.80$ \kmsMpc. % and from Planck results, $H_0=67.3\pm1.2$\kmsMpc, but smaller than other recent determinations based on Cepheidcalibration for SNe Ia luminosity, $H_0 = 74 \pm3$ km s$^{-1}$ Mpc$^{-1}$.

The Tip of the Red Giant Branch Distances to Type Ia Supernova Host Galaxies. II. M66 and M96 in the Leo I Group