It might be possible to work this in your head. Your 98 is 100 minus 2. This means 98 plus 98 is 100 plus 100 minus 2 minus 2. That's 200 minus 4 which gives 196 as the answer.
1.2 billion minus 3.2 million = 1.1968 billion
1.2 billion minus 312 million is 888,000,000
7 billion minus 900 million = 6,100,000,000
7 billion minus 5 million is 6,995,000,000
It might be possible to work this in your head. Your 98 is 100 minus 2. This means 98 plus 98 is 100 plus 100 minus 2 minus 2. That's 200 minus 4 which gives 196 as the answer.
999,999,998,000,000,000
1.2 billion minus 3.2 million = 1.1968 billion
9,800,000,000
4.6 billion
98 - 69 = 29
1.2 billion minus 312 million is 888,000,000
7 billion minus 900 million = 6,100,000,000
7 billion minus 5 million is 6,995,000,000
3.9 billion minus 346 million = 3,554,000,000
2.8 billion minus 142 million is 2,658,000,000
6.4 trillion minus 6 billion is 6,394,000,000,000