On Monday, a person mailed 8 packages weighing an average of 1238 pounds and on Tuesday, 4 packages weighing an average of 1514 pounds. What was the average weight, on pounds, of all the packages the person mailed on both days?
A
2734
B
1313
C
1312
D
2714
Correct Answer: 1313
Total weight of packages mailed on the 1st day = <math xmlns = "http://www.w3.org/1998/Math/MathML"><mn>12</mn><mfrac><mn>3</mn><mn>8</mn></mfrac><mo>×</mo><mn>8</mn><mo> = </mo><mn>99</mn><mo> </mo><mi>p</mi><mi>o</mi><mi>u</mi><mi>n</mi><mi>d</mi><mi>s</mi></math>Total weight of packages mailed on the 2nd day = <math xmlns = "http://www.w3.org/1998/Math/MathML"><mn>15</mn><mfrac><mn>1</mn><mn>4</mn></mfrac><mo>×</mo><mn>4</mn><mo> = </mo><mn>61</mn><mo> </mo><mi>p</mi><mi>o</mi><mi>u</mi><mi>n</mi><mi>d</mi><mi>s</mi></math><math xmlns = "http://www.w3.org/1998/Math/MathML"><mo>∴</mo></math> Average weight = <math xmlns = "http://www.w3.org/1998/Math/MathML"><mfrac><mrow><mn>99</mn><mo> + </mo><mn>61</mn></mrow><mrow><mn>8</mn><mo> + </mo><mn>4</mn></mrow></mfrac><mo> = </mo><mn>13</mn><mfrac><mn>1</mn><mn>3</mn></mfrac><mo> </mo><mi>p</mi><mi>o</mi><mi>u</mi><mi>n</mi><mi>d</mi><mi>s</mi></math>