1.1 billion is written as 1,100,000,000. Because 1 billion has nine zeros in it, you can simply move the decimal point nine places to the right to get your answer of 1,100,000,000.
17.9 billion written out in numbers is 17,900,000,000
1,000 billion billion is: 1,000,000,000,000,000,000,000
153.4 billion = 153,400,000,000
4.2 billion = 4,200,000,000
It is: 900,000,000 = 0.9 billion
1.52 billion written in numbers is 1,520,000,000
17.9 billion written out in numbers is 17,900,000,000
1,000 billion billion is: 1,000,000,000,000,000,000,000
15.8 billion = 15,800,000,000
Six billion = 6,000,000,000
153.4 billion = 153,400,000,000
3,900,000,000 is 3.9 billion.
It is: 124,000,000,000 = 124 billion
4.2 billion = 4,200,000,000
It is: 900,000,000 = 0.9 billion
2,280,000,000 = 2.28 billion
It is: 25,300,000,000 = 25.3 billion