SOLUTION: Hi. How can I solve this? Thanks. Both Mr Gan and Mr Koon received a salary every month. Last month, Mr Gan's salary was 9/10 of Mr Koon's salary. This month, Mr Gan's salary decr

Algebra.Com
Question 1201373: Hi. How can I solve this? Thanks.
Both Mr Gan and Mr Koon received a salary every month. Last month, Mr Gan's salary was 9/10 of Mr Koon's salary. This month, Mr Gan's salary decreased by $220 while Mr Koon's salary increased by $200. In the end, Mr Gan's salary was 7/10 of Mr Koon's salary. What was Mr Gan's salary last month?
Found 3 solutions by josgarithmetic, MathTherapy, greenestamps:
Answer by josgarithmetic(39620)   (Show Source): You can put this solution on YOUR website!
              Lastmonth          Thismonth

Gan            0.9k              0.9k-220

Koon            k                 k+200

"In the end" must mean, "This Month".

----------literally according to the description.
.
.
Use found k to evaluate 0.9k.
Answer by MathTherapy(10552)   (Show Source): You can put this solution on YOUR website!
Hi. How can I solve this? Thanks.
Both Mr Gan and Mr Koon received a salary every month. Last month, Mr Gan's salary was 9/10 of Mr Koon's salary. This month, Mr Gan's salary decreased by $220 while Mr Koon's salary increased by $200. In the end, Mr Gan's salary was 7/10 of Mr Koon's salary. What was Mr Gan's salary last month?

Let Gan's salary, last month, be G
Since last month, Mr Gan's salary was  of Mr Koon's salary, Mr. Koon's salary, last month, was 
With Gan's salary decreasing by $220, Gan's salary, this month, is G - 220.
With Koon's salary increasing by $200, Koon's salary, this month = 

As Gan's salary, this month, was  of Koon's, this month, we get:  
                                                                 9(G - 220) = 7G + 140(9) ------ Cross-multiplying
                                                                9G - 220(9) = 7G + 140(9)
                                                                    9G - 7G = 140(9) + 220(9)
                                                                         2G = (140 + 220)(9)
                                                                         2G = 360(9)
                                 Mr. Gan's salary, last month, or

Answer by greenestamps(13200)   (Show Source): You can put this solution on YOUR website!


You CAN solve the problem using fractions or decimals, as shown in responses from other tutors. But the actual work to solve the problem is usually easier if we can set the problem up using whole numbers.

Since last month Mr Gan's salary was 9/10 of Mr Koon's salary...

let 9x = Mr. Gan's salary last month
let 10x = Mr. Koon's salary last month

When Mr. Gan's salary decreased by $220 and Mr. Koon's salary increased by $200, Mr. Gan's new salary was 7/10 of Mr Koon's new salary:







ANSWER: Mr. Gan's salary last month was 9x = 9($180) = $1620
RELATED QUESTIONS

Mr. Bailey's salary was $3,300,000 after he had received an increase of 10%. Calculate... (answered by josgarithmetic)
Last month, Alex spent 40% of his salary on a laptop. He then spent 30% of it on his... (answered by oberobic)
Can u please help me answer this question Mr khan gets a 10% raise in salary every year. (answered by josgarithmetic)
(a) the ratio of mr paul's salary to mrs anna's salary is 3:4. if mrs anna draws a salary (answered by mananth,greenestamps,ikleyn,josgarithmetic)
If the salary for of A is 16000/- for this month which is 10% more than last month... (answered by ewatrrr)
Mr Ahmed earns Rs 25000 per month. He spend 2/5 of his salary on utility bills, 1/10 on... (answered by mexicanchickadee)
The monthly salary of Mr.Gill is the same each month. In November, Mr Gill spent $1600... (answered by ikleyn)
Mr Tan saved a portion of his salary every month .Each month ,he saved 120% of what he... (answered by jorel555)
Hi Rashna saves 20% of her salary every month. When her salary increases by 10% her... (answered by ikleyn,Edwin McCravy,greenestamps)