Shib'im (70) Versus Hamishshim (50) and Daniel's 70 Weeks

Shib’im is literally 70 (ten sevens), as the numbering system in Hebrew is base 10, as is said, “Shib'im Panim la-Torah" (Seventy Methods of the Explanations of the Torah)” – The Jubilee, the 50th year (not 49th year which you would get by multiplying 7 x 7 under your method), is not referred to as shib’im, as that would mean 70, not 50 – you are confusing hamishshim (means 50) with shib’im, two completely different words, as is evidence in a comparison to Leviticus 25:10 (which defines the Jubilee in terms of hamishshim) to Daniel 9:24 (which speaks not of hamishshim, but rather shib'im) – they are separate cardinal numbers.

Hamishshim (50) comes from the root hamash (fifth), whereas shib’im (70) comes from the root sheba (seven).