Coins in a money box

Karol has in his money box in total 19 coins, and only ten-crown and fifty-crown coins. In total he has in the money box 830 Kč saved.
Which statement is false? (Provide a solution procedure for the individual statements.)
a) In the money box 170 Kč (Czech crown) are missing to a thousand.
b) In the money box there are fewer ten-crowns than fifty-crowns.
c) In the money box there are 13 more fifty-crowns than ten-crowns.
d) In the money box there is an equal number of ten-crowns and fifty-crowns.
e) In the money box the ten-crowns and fifty-crowns are in the ratio 3 : 16 (in this order).

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