Han, his sister, his dad, and his grandmother step onto a crowded bus with only 3 open seats for a 42-minute ride. They decide Han’s grandmother should sit for the entire ride. Han, his sister, and his dad take turns sitting in the remaining two seats, and Han’s dad sits 1.5 times as long as both Han and his sister. How many minutes did each one spend sitting?

Han= 24 minutes

His sister= 24 minutes

His Dad= 36 minutes

Grandmother= 42 minutes

Step-by-step explanation:

Please see attached picture for full solution.

Where the working split, see the right hand side.

The question states that Han's Dad sits 1.5 times as long as both Han and his sister. There could be 2 interpretations for this:

- Dad sits for 1.5 times of (Han and his sister)

- Dad sits for 1.5 times of Han and 1.5 times of Han's sister

I've done the working for both scenarios and found out that the 1st case cannot be true since Dad would've sat for 50.4 minutes when the bus ride is only 42 minutes! Moreover, there wouldn't be enough information to know how long Han and his sister sat for.

The second case is possible and it's working is on the right.

Feel free to ask if you have any enquiries :)

a_n = a_1 + (n - 1)d

the first term is 6.

the common difference d = ?

when you find d, replace n with 7 and d with the common difference to find your answer.