Spelling mistakes in a text are either "nonword errors" or "word errors." A nonword error produces a string of letters that is not a word, such as "the" typed as "teh." Word errors produce the wrong word, such as "loose" typed as "lose." Nonword errors make up 25% of all errors. A human proofreader will catch 80% of nonword errors and 50% of word errors. What percent of errors will the proofreader catch?

The proofreader will catch 57.5% of errors

Step-by-step explanation:

Since non-word errors: 25% of all errors (given)

Hence, word errors: 75% of all errors (remaining)

Remember, statements that say "a of b", the word 'of' indicates a multiplication operation!

80% of 25% means ×

= 0.8 × 0.25 = 0.2

50% of 75% means ×

= 0.5 × 0.75 = 0.375

And now just add the two answers together to get the total errors detected

0.2 + 0.375 = 0.575

Multiply this value by 100 to convert to a percentage value

0.575 × 100 = 57.5%

Have a great day! :)