The sum of digits of a two digit number is 9. The sum of the number and the number obtained by interchanging the digits is 99. If the total worth of the coins is $1.80, how many are there of each? A c...The sum of digits of a two digit number is 9. The sum of the number and the number obtained by interchanging the digits is 99. If the total worth of the coins is $1.80, how many are there of each? A company is analyzing sales reports for three products: products X, Y, Z. One report shows that a combined total of 20,000 of items X, Y, and Z were sold. Another report shows that the sum of the number of item Z sold and twice the number of item X sold equals 10,000.