It is 300000.
It is front-end estimation.
It is 3000000000.
27.60 rounded to one decimal place is 27.6. The first digit to the right of the . is the tenth.
As the second digit is a 5, it will round up to give:0.3
To round off 128,674 to leave one nonzero digit, you would round it to 100,000.
0.2.
It is 400.
It is 300000.
It is 6000000.
It is 300.
It is 500.
It is front-end estimation.
500
It is 90000.
500500
It is 5000000.