You are given a math word problem and you are supposed to apply addition or subtraction mathematical operators on the numbers embedded in the text to answer the following question and then only report the final numerical answer.

Irwin 's family went on a camping trip in the mountains . On the first day , they hiked from their car to the campsite . First , they hiked 0.2 mile from the car to a stream , and 0.4 mile from the stream to a meadow . Then they hiked 0.1 mile from the meadow to the campsite . How many miles did Irwin 's family hike in all ?
0.7

64 children were riding on the bus . At the bus stop , some more children got on the bus . Then there were 78 children altogether on the bus . How many children got on the bus at the bus stop ?
14

Donald has 4 oranges . He finds another 5 . How many oranges does Donald have in all ?

9