Answer: Alexia completed 20 math problems and 10 science problems.
First and mainly keep that 9 one side,
There are 2 people involved Ann and Betty, Then divide the TOTAL AMOUNT BY THE NUMBER OF PEOPLE.
· Then it will look like $60÷2= $30 per person.
In this case everyone has equal amount of money, but the question say Ann has $9 more than Betty's. so, Ann≈ $30 +$9= $39.
Betty≈ $30-$9= $21
Because loses money because Ann has more,
TOTAL=Ann+Betty
$60= $39+$21
They started at 453, then climbed 162, so now they are at:
453 + 162 = 615 feet.
They then cllmb another 207 feet to get to:
615 + 207 = 822 feet.
They then descend ( climb down) 285 feet.
822 - 285 = 537 feet.
Now they need to get back tot he original 453,
so they have to descend:
537 - 453 = 84 more feet.
The answer is C.
The sum means adding, so your answer is f + 6