The average age of six children is 13 years and 5 months. a seventh child joins the group, increasing the average age by two months. how old is this seventh child idk

14 years 7 months

Step-by-step explanation:

If the average age was increased by 2 months by adding a 7th child, the total age was increased by 2·7 months = 14 months more than the previous average. That is, the added child's age is 14 months more than the previous average, so is ...

... (13 years + 5 months) + (1 year + 2 months) = 14 years + 7 months

For the non-believers:

The previous total of all ages was ...

... 6 × (13 years 5 months) = 80 years 6 months

The new total of all ages is ...

... 7 × (13 years 7 months) = 95 years 1 month

The amount added to the previous total is ...

... (95 1/12 - 80 6/12) years = 14 7/12 years = 14 years 7 months

b.

step-by-step explanation:

i just know

you estimate that the angle of elevation to the top of the 86th floor (the observatory) is 82 .the total height of the building is another 123 meters above the 86th floor.

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