Answer:
a. We spent all together 40.2+24.5+37.8=$102.50.
b. We saved 19.8+10.5+7.2=$37.50
c. 
Step-by-step explanation:
To find the amount we spend, we multiply the original price by the decimal conversion of each fraction. Then we add the amounts together.
- Sneakers cost $60 and you bought them at 2/3=0.6666....
60(0.67)=$40.20 and saved $19.80
- Sweater costs $35 and you bought it at 7/10=0.7
35(0.7)=$24.50 and saved $10.50
- A jacket costs $45 and you bought it at 5/6=0.8333...
45(0.84)=$37.80 and saved $7.20
We spent all together 40.2+24.5+37.8=$102.50.
We saved 19.8+10.5+7.2=$37.50
We could of spent paying regular price 60+35+45=$140. To find the fraction we place the total we actually paid over the total regular price.

Answer:
7542.96
Step-by-step explanation:
Answer:
Every week, the radioactivity decreases by a factor of 5
After 1 week, it goes from 5,000 to 1,000
2 weeks 1,000 / 5 =200
3 weeks 200 / 5 = 40
4 weeks 40 / 5 = 8
5 weeks 8 / 5 = 1.6
6 weeks 1.6 / 5 = 0.064
7 weeks 0.064 / 5 = 0.0128
8 weeks .0128 / 5 = 0.00256
9 weeks 0.00256 / 5 = 0.000512
10 weeks 0.000512 / 5 = 0.0001024
Step-by-step explanation: