Question

In October 2009,there were approximately 5x10^7 members of a website. In January 2013, there were approximately 2x10^8 members. How many more members were there in January 2013 than in October 2009? Write your answer in scientific notation. There were__________more members in January 2013 than in October 2009.

Answer 1

`There\ were\ 1.5* 10^8\ more\ members\ in\ January\ 2013\ than\ in\ October\ 2009.`

Explanation:

`Number\ of\ members\ in\ October\ 2009=5* 10^7\\\\Number\ of\ members\ in\ January\ 2013=2* 10^8\\\\Number\ of\ members\ in\ January\ 2013=2* 10* 10^7\\\\Number\ of\ members\ in\ January\ 2013=20* 10^7`

More members in January 2013=Number of members in January 2013-Number of members in October 2009.

`The\ number\ of\ members\ that\ are\ more\ in\ January\ 2013=20* 10^7-5* 10^7\\\\The\ number\ of\ members\ that\ are\ more\ in\ January\ 2013=(20-5)* 10^7\\\\The\ number\ of\ members\ that\ are\ more\ in\ January\ 2013=15* 10^7\\\\The\ number\ of\ members\ that\ are\ more\ in\ January\ 2013=1.5* 10* 10^7\\\\The\ number\ of\ members\ that\ are\ more\ in\ January\ 2013=1.5* 10^8\\\\There\ were\ 1.5* 10^8\ more\ members\ in\ January\ 2013\ than\ in\ October\ 2009.`