# algebra

In 1920 the record for a certain race was 46.5 seconds. in 1980 it was 45.3 seconds let R(t) = the record in the race and t=the number of years since 1920

R(t) = 46.5 - t*0.02
what is the predicted record in 2003? 44.84
what is the predicted record in 2006?44.78
what year will the record be 44.58 seconds? 2015
help me figure this out, first I subtract 46.5 - 45.3 = 1.2 next 1980- 1920 = 60 1.2/60 = 0.02
are these correct

1. 👍 0
2. 👎 0
3. 👁 82
asked by kelly
1. t = year - 1920

r = m t + 46.5

in 1980 t = 1980 - 1920 = 60

r = m (60) + 46.5 = 45.3
so
m = (45.3-46.5)/60 = -0.02
so
r = -0.02 t + 46.5 Our equation agreed

in 2003:
t = 2003 - 1920 = 83 years
r = -0.02 (83) + 46.5 = 44.84 agree

now for example in what year will it be 44 seconds?

44 = -0.02 t + 46.5
0.02 t = 46.5 - 44 = 2.5
so
t = 125
125 = year - 1920
so year = 2045 (that is just an example so you can do the real problem.)

1. 👍 0
2. 👎 0
posted by Damon

## Similar Questions

1. ### Algebra

In 1920, the record for a race was 46.9 seconds. In 1940 it was 46.5 seconds. Let R(t)= the record in the race and t= the number of years since 1920. a) Find a linear function that fits data. b)Predict the records for 2003 and

asked by Autumn on February 28, 2012
2. ### Intermediate Algebra

in 1920 the record for a certain race was 45.7 seconds. In 1930, it was 45.4 seconds. Let R(t)= the record in the race and t = the number of years since 1920. Find the linear function that fits the data.R(t)=__ (round to nearest

asked by Vienna on December 16, 2010
3. ### algebra

ok i don't get this one in 1920 the record for a certain race was 45.9 sec in 1980 it was 44.1 sec let r (T) = the record in the race and t= the number of years since 1920 (a) find a linear fuction that fits the data (b) use the

asked by need help please on December 20, 2009
4. ### Algebra 1

in 1920, the record for a certain race was 45.8 sec. In 1980, it was 44.6 sec. Let R(t)=the record in the race and t=the number of years since 1920. find the linear function that fits the data use the function (a) to predict the

asked by Need Help on September 22, 2009
5. ### Math

how do I solve this problem. In 1920 the record for a certain race was 445.7 sec. In 1970, it was 44.2 sec. Let R(t) = the record in the race and t = the number of years since 1920. a) Find a linear function that fits the data

asked by lisa on September 26, 2010
6. ### Math

In 1920, the record for a certain race was 46.6 sec. In 1980, it was 45.4 sec. Let R(t)= the record in the race and t = the number of years snce 1920. a) Find a linear function that fits the data R(t) = b) Use the function in (a)

asked by Liz on March 11, 2010
7. ### math

In 1920 the record for a certain race was 46.6 sec. In 1950 it was 46.0 sec. let r(t)= the record in the race and t= the number of years since 1920. (a) find a linear function that fits the data r(t)= (round to the nearest

asked by billy on November 2, 2008
8. ### Math 116

In 1920, the record for a certain race was 45.7 sec. In 1950, it was 45.1 sec. Let Ra9ta0=the record in the race and the number of years since 1920. A. Find a linear function for the data B. Use the function in (a) to predict the

asked by Kim on May 27, 2011
9. ### math

someone plz help me.... In 1920 the record for a certain race was 46.6 sec. In 1950 it was 46.0 sec. let r(t)= the record in the race and t= the number of years since 1920. (a) find a linear function that fits the data r(t)=

asked by billy on November 2, 2008
10. ### math plz help

someone plz help me.... In 1920 the record for a certain race was 46.6 sec. In 1950 it was 46.0 sec. let r(t)= the record in the race and t= the number of years since 1920. (a) find a linear function that fits the data r(t)=

asked by billy on November 2, 2008

More Similar Questions