Answer:
30
Step-by-step explanation:
Step 1) turn 1.9 into an improper fraction.
= 19/10
step 2) find a least common denominator between 10 and 12.
= 60
(10x6 and 12x5)
step 3) convert the fractions so they have the same denominator.
= 19x6 is 114.
10x6= 60.
= 11x5 is 55.
12x5 is 60.
now you have your new fractions.
step 4) subtract.
= 114/60 - 55/60 is 59/60.
step 5) simplify.
the answer is either 0.9833... (3 repeating) or just 59/60 (you can't simplify the fraction any further).
Total divided by number of rows=number per row
63/7=9
9 per row
If 
is a number that is both divisible by 4 and 5, then
4 and 5 are coprime, so we can use the Chinese remainder theorem to solve this system and find that 
is a solution to the system, where 
is any integer. Simply put, any multiple of 20 fits the bill.
Now, there are 11 numbers between 100 and 300 that are divisible by 20 (100, 120, 140, and so on). We have 
when 
, so the sum we want to compute is
