# math...please help asap

posted by
**anonymous**
.

Solve the following; use proper fractions in your answer:

1. 1/3 + 1/4 = 7/12

2. 4/5-2/3 = 2/15

3. 5/6 * 4/5 = 2/3

4. 3/7 divided by 6/8 = 4/7

5. 3 1/4 - 1 3/8 = 1 7/8.....is this a proper fraction?

6. 5 8/9 + 2 4/7 = 8 29/63..is this a proper fraction?

Reduce the following:

7. 15/9 = 5/3

8. 43/17 = 43/17

Conversions:

9. 13 centimeters =? meters

0.13 meters

10. 2.3 yards = ? inches

82.8 inches

11. 2 gallons = ? cups

32 cups

12. 15 years = ? seconds

473,040,000 seconds

13. 53 ounces = ? pounds

3.3125 pounds

Scientific Notation

Write the follow in proper scientific notation:

14. 3,141,592

3.141592 * 10 ^6

15. 437.234

4.37234 * 10^5

16. 0.004567

4.567 * 10^-3

Write the number in non-scientific notation:

17. 6.02 * 10^4

60200

18. 9.8 * 10^-2

.098

Solve the following in scientific notation:

19. 4.567 * 10^4 + 2.156 * 10^5

Answer: 2.61270*10^5 or would it be 10^4 since there is a zero on the end

20. (2.87*10^12)(1.56*10^3)

Answer: 4.4772*10^12???????? I'm not sure about the exponent on this one.

Percentages:

21. 25% of 36 is what numer? 9

22. 25 is what % of 125? 20%

Manipulating and Solving Equations:

Solve for the unknown in the following equation: d = 1/2gt^2

23. g = 2, t=4, d=?

d = 16

24. d=10, g=5, t=?

t=2

Solve the following eqeations for x:

25. 2x = 14

x=7

26. 3x+2y = 32

x= -2/3y+32/3

27. g=3yx^2

x = the square root of 9/3y

28. 12x/y = 3y

x= y^2/4

do u want to know if u are right?

7 increased by x