OpenStudy (anonymous):

Word Problem help please 1. The magician said "The average of seven numbers is 49. If 1 is added to the fisr number, 2 is added to the second number, 3 is added to the third number and so on up to seventh number". what is the new average ?

6 years ago
OpenStudy (anonymous):

can u help

6 years ago
OpenStudy (ksaimouli):

11 is the average

6 years ago
OpenStudy (anonymous):

step by step because i have no idea how u got that

6 years ago
OpenStudy (anonymous):

\[49=\frac{x_1+x_2+...+x_7}{7}\] \[\frac{x_1+1+x_2+2+..+x_7+7}{7}=\frac{x_1+x_2+...+x_7+28}{7}\] \[=49+\frac{28}{7}=49+4=53\]

6 years ago
OpenStudy (anonymous):

oh kk i have another word problem could u people help me

6 years ago
OpenStudy (anonymous):

snaap ...

6 years ago
jimthompson5910 (jim_thompson5910):

The average is equal to the sum of all the numbers divided by the number of numbers. So if the numbers add up to some number S, then the average A is A = S/7 But we know that the average is 49, so A = 49, which means that A = S/7 49 = S/7 49*7 = S 343 = S So S = 343 Since we're adding 1 to the first, 2 to the second, etc all the way up to 7 to the seventh, we're basically adding 1+2+3+4+5+6+7 = 28 to S to get S+28, which means that the new sum is now S+28 = 343 + 28 = 371 Now divide this new sum by 7 to get 53 So the new average is 53

6 years ago
OpenStudy (anonymous):

wait im getting confused ?

6 years ago
OpenStudy (anonymous):

(49*7+28)/7=53

6 years ago
OpenStudy (anonymous):

\[x_1+1+x_2+2+x_3+3+...+x_7+7 \] \[(x_1+x_2+..+x_7)+(1+2+3+4+5+6+7)\]

6 years ago
OpenStudy (anonymous):

whats the real answer

6 years ago
OpenStudy (anonymous):

11 or 53

6 years ago
OpenStudy (anonymous):

53

6 years ago
OpenStudy (anonymous):

satellite and jim's 53

6 years ago
OpenStudy (anonymous):

kk can u help with another one

6 years ago
OpenStudy (anonymous):

kk can u help with another one

6 years ago
OpenStudy (anonymous):

anybody

6 years ago
OpenStudy (anonymous):

You can post a new question so all can see it.

6 years ago
OpenStudy (anonymous):

kk in a given school, there 240 boys and 260 girls ...what is the ratio of numbers of girls to the number of boys ...what is the ratio of the number of boys to the total number of pupils in the school?

6 years ago
OpenStudy (anonymous):

ratio of girls to boys = 260 / 240

6 years ago
OpenStudy (anonymous):

ratio of boys to total pupils = 240 / (240+260) = 240 / 500

6 years ago
OpenStudy (anonymous):

?? for first ? what isnt that just telling me girls to boys 260/240??

6 years ago
OpenStudy (anonymous):

ok so ready for next ?

6 years ago
OpenStudy (anonymous):

why don't you ask a new question ?

6 years ago
OpenStudy (anonymous):

1. if tim had lunch at $50.50 and he gave 20% tip. how much did he spend? 2. Find the greatest common factor of 24, 40 and 60 ? 3. in 2008 , the world population is about 6,760,000,000. Write the 2008 wolrd population in scientific notation 4. give the rules of divisibility ?

6 years ago
OpenStudy (anonymous):

some of the rules

6 years ago