Answer:
Mr. Lang bought a coat and a pair of gloves for each of his 13 grandchildren, so he bought 13 coats and 13 pairs of gloves.
Each coat cost $30, so the total cost of the coats was 13 coats * $30/coat = $<<13*30=390>>390.
Each pair of gloves cost $6.49, so the total cost of the gloves was 13 gloves * $6.49/glove = $<<13*6.49=84.37>>84.37.
The total cost of the coats and gloves was $390 + $84.37 = $<<390+84.37=474.37>>474.37.
Therefore, Mr. Lang's total purchase was $474.37.
Explanation: