Math Questions..Please help...?

Question

1. Change 13 2/5 to an improper fraction?
2. Write 17/51 in simpliest form?
3. 5/21 x 14/25= in simpliest form?
4. 4 1/5 x 10/21x 9/20=
5. in proper units 5lb/ft x 3ft=

Answer 1

Oh god please stop. You are bringing back memories I repressed long ago.

Answer 2

1. An improper fraction is "top-heavy" -- the numerator is greater than the denominator. And, since 13 is 65/5... then 13 2/5 is
67/5

2. 17/51 = 1/3. Since 17 is prime, the only way to reduce a fraction with 17 as the numerator is to divide both numbers by 17.

3. The easy way to get fractions in their simplest form is to factor each one out, and then eliminate matches. So, 5 = 5, 21 = 3*7, 14 = 2*7, 25 = 5*5. When multiplying fractions, you multiply numerators and denominators separately, so...
(5*2*7) / (3*7*5*5)
One five and one seven will both cancel (5/5 = 7/7 = 1 and anything times 1 is itself), leaving
(2) / (3*5) = 2/15

4. This goes back to problem 1. The best way to multiply mixed is to change them to improper fractions. 4 1/5 = 20+1/5 = 21/5

(3*7)/(5) * (5*2)/(3*7) * (3*3)/(2*2*5)
(3*7*5*2*3*3) / (5*3*7*2*2*5)
(2*3*3*3*5*7) / (2*2*3*5*5*7)
One set each of twos, threes, fives, and sevens will cancel each other out, leaving.

(3*3)/(2*5) = 9/10

5. Labels cancel out the same way numbers do. You could consider them (for these purposes, at least) as constants, symbols that signify something that doesn't change.
5lb/ft * 3ft
3*5 lb*ft / ft
15 lb

Answer 3

13 2/5 = 67/5
17/51 = 1/3
5/21 x 14/25 = 2/15
4 1/5 x 10/21 x 9/20 = 9/10
5lb/ft x 3ft= = 15 lb

Answer 4

1) 67/5, you multiply 5x13=2 which is where i got the 67, all over the original denominator=5

2) 1/3, 17 can go into 17 once=numerator, & 17 can go into 51 three times=denominator.

3-5) to much brainwork, i have statistics homework so I better focus my energy on that! :)

and the commment about #2 being in simplest form because 17 is prime is total BS.

Answer 5

ans 1: 67/5
=((5 x 13)+2)/5

ans 2: 1/3
= (17 x 1)/(17 x 3)
= 1/3

ans 3: 2/15

ans 4: 9/10

ans 5: check for unit conversion and convert lb/ft into ft u will get the answer

Answer 6

Now, I don't usually help people with these stupid of questions. but...
1) 67/5
2) 17 is prime, so it's already in simplest form
Screw 3 and 4
5) 15lb/3ft?

Answer 7

1 65/5
2 it is in simp. form
3
4
5 15 lbs.

Answer 8

I used to find all that easy to do but I forgot how now because I never had to use that math in my life. Sorry.

Answer 9

Ditto to the answer above me-My brain is tired