In two or more complete sentences, describe how you could model the following sum on a number line. In your answer, make sure to include the result of adding these two numbers together. -3.5 + 4.2

The first week samantha learned to read braille, she could read 10 words per minute. in the second week she increased her speed by 20%. in the third week she increased her speed again by another 25%. how many words could she read per minute by the third week? hurry and tell me!