Answer
1 hundred and 9 tens
Explanation
19 tens is the same as ten times 19, so:
19 tens = 10 x 19
Remember that to multiply any number by 10 or 100 we just need to attach the zeros to the number, so:
10 x 19 = 190
Now let's check which one of our given choices is equivalent to 190:
10 hundreds and 9 tens
10 hundreds is ten times a hundred, so: 10 x 100 = 1000
9 tens is 9 times ten, so: 9 x 10 = 90
Now we just need to add them both:
10 hundreds and 9 tens = 1000 + 90 = 1090
1090 is not equal to 190, so this choice is wrong.
1 hundred and 9 tens
1 hundred is one time one hundred so: 1 x 100 = 100
9 tens is 9 times ten, so: 9 x 10 = 90
Now we just need to add them both:
1 hundred and 9 tens = 100 + 90 = 190
This is our guy!
We can conclude that 19 tens is 1 hundred and 9 tens
9 hundreds and 1 ten
9 hundreds is 9 times one hundred, so: 9 x 100 = 900
1 then is 1 time then, so: 1 x 10 = 10
9 hundreds and 1 ten = 900 + 10 = 910
Wrong choice.
1 hundred and 9 ones
1 hundred is 100
9 ones is 9
1 hundred and 9 ones = 100 + 9 = 109
Wrong choice.