Answer:
D. $32.67
Step-by-step explanation:
Can you go into detail about what you need help with?
1a. 21/3+32/5
((2*3)+1)/3+((3*5)+2)/5
7/3+17/5
(7*5+17*3)/15
86/15
1b. 2/3+3/5+2/5
(2*5+3*3+2*3)/15
(10+9+6)/15
25/15
5/3
2a. 57/10-22/5
(5*10+7)/10-(2*5+2)/5
57/10-12/5
(57*1-2*12)/10
33/10
2b. 5/12-1/4
(5*1-1*3)/12
2/12
1/6
3 say she has x stamps,she gave 2/9 and 1/5 to her frends so she is left with
X-2x/9-x/5
(9*5x-5*2x-9*1x)/45
(45x-10x-9x)/45
26x/45
4. 7/10+1/5
(1*7+2*1)/10
9/10
5. Brick 21/3kg
Stone (2*3+1)/3-(1*10+1)/10
7/3-11/10
(7*10-3*11)/30
(70-33)/30
37/30
To reduce<span> a </span>fraction to lowest terms<span> (also called its simplest form), divide both the numerator and denominator by the GCD. For example, 2/3 is in </span>lowest<span> form, but 4/6 is not in </span>lowest<span> form (the GCD of 4 and 6 is 2) and 4/6 can be expressed as 2/3.
38/80= 19/40</span>
<h3>
Answer: They're all the same</h3>
====================================================
Reason:
means we have 6 copies of "2" multiplied out as shown in choice B. That explains how A and B are the same, and we can say

The parenthesis are optional, but I find they're handy to count the '2's easier.
----------------
Now notice that

So,

The last step is possible because we have two copies of
multiplied together.
This shows that choice C is equivalent to A and B.
-------------------
Lastly,

The jump to the last step is possible because we have three copies of
multiplied together.
This shows choice D is equivalent to the others.
All four expressions are the same.
They represent different ways to say the same number. That number being 64.