Afast typist can type 120 words in 100 seconds. at that rate, how many seconds would it take to type 258 words?

215 seconds

Step-by-step explanation:

120 words : 100 seconds = 258 words : x seconds

x = 258*100/120 = 258*5/6 = 43*5/1 = 215 seconds

120+120+ 18= 258

You know that it takes 100 seconds for 120 words

120=100 120=100 now we have to find now how many seconds does it take to make 18 words

step-by-step explanation:

the original amount doesn't ''re just looking for the time it takes for 1/2 of the substance to we have

(1/2) =)     take the ln   of both sides

ln (1/2)   = )   and we can write

ln(1/2) = ) lne     and lne   = 1     so we have

ln(1/2) = -.1092t     divide both sides by -.1092

t = ln(1/2)/-.1092 = about 6.347 days = about 6.3 days (rounded)