Explanation:
a ratio a:b means that there are in total (a + b) equally sized packages in the whole, and the first party has a of these (a + b) packages, and the second party has b of the (a + b) packages.
here we have a ratio of 6:7.
and we know that the 6 packages of Samuel have a total value of $60.
that means one of these packages has the value of
60 / 6 = $10.
now, Maria has 7 of these $10 packages.
that means she has
7 × 10 = $70
Maria has $70.