Rob is saving to buy a new MP3 player. For every $12 he earns babysitting, he saves $9. On Saturday, Rob earned $48 babysitting. How much money did he save?

What number produces an irrational number when multiplied by -1.25

If the scale factor between two circles is 2x/5y what is the ratio of their areas?

Lizette is training for a marathon. at 7: 00 she left her house and ran until 8: 30, then she walked until 11: 30. she covered a total distance of 18 miles. her running speed was six miles per hour faster than her walking speed. find her running and walking speeds in miles per hour.