Fraction is bigger than size, half and four fifths are bigger than size, or equal

Fraction is bigger than size, half and four fifths are bigger than size, or equal

1/2=5/10
4/5=8/10
Because 5 / 10 is less than 8 / 10
∴ 1/2 ＜4/5
A: one half is less than four fifths

What's half of two fifths?

Multiplying two fifths by one half equals two tenths, and reducing it to one fifth

One third by three fifths plus one half by three fifths

Add one third and one half to get five sixths, then multiply by three fifths to get one half

Compare the size of two numbers in the following groups. (1) negative half, one third (2) negative three seventh, two fifths

(1) A negative half, a third, a positive number is always greater than a negative number, so a negative half is less than a third
(2) Negative three out of seven, negative two out of five, negative number is bigger but smaller, so negative three out of seven is bigger than negative two out of five