Solve. (1 1/2 x 3 3/4) - ( 2 3/5 / 1 1/2)

First convert the mixed numbers to improper fractions 

= (3/2 * 15/4) - (13/5 * 3/2)

=  45/8 - 39/10

=  225/40 -  156/40

=   69/40

= 1 29/40 Answer

For that answer i got 3 -2/120 but I'm not sure about it

A1 is the 1st term  r is the difference, they can say "r" or "d" for the difference   1st a1 is the first term = -3 2nd "r" is the difference between each consecutive terms (coming after each other) = 1.5 the rule to get any term of the sequence as we add 1.5 each time is --> a1+(n-1)*d  a1 --> 1st term , n --> order of the term u want whether 2nd, 3rd , 25th  d --> difference  so to get the 2nd-->    -3+(2-1)*1.5= -1.5 to get the 3rd -->        -3 +(3-1)*1.5 = 0  and so on