One thing we must always remember that when we have number 0 after the decimal point, it means we do not need to consider that as it will have no effect on product and on the other operations.
So,
1)
17.4 x 1.0 = 17.4 x 1 = 17.4 (Product is equal to 17.4)
2)
Suppose if a number 'A' which is less than 1 is multiplied by any other number 'B', than the multiplication always result in the number less than B.
For example:
1x0.5 = 0.5 which is less than 1
Similarly for
17.4 x 0.98 = Result will be less than 17.4 as the second number is less than 1.
