Current location - Training Enrollment Network - Mathematics courses - I'd like to ask you some math problems in grade four, thank you! Can you help me? Because the final exam is coming, help me solve the problem!
I'd like to ask you some math problems in grade four, thank you! Can you help me? Because the final exam is coming, help me solve the problem!
① Solving equation: x/2.5 = 8028 * a can be written as (8a) or (A8); (3) comics, story books each 9.5 yuan, 8.5 yuan; It costs (9.5a+8.5b) yuan to buy a comic book and a story book; ④ The side length of a square plate is 1 decimeter, the perimeter is (4a) decimeter, and the area is. ⑤ Naughty family spends N yuan on water and electricity in February, and his family spends (n÷28) yuan on water and electricity this month. There are m apple trees in the orchard, twice as many as peach trees, and (2m) peach trees. Liu Xing is one year old, so she was (a-3) years old three years ago.

That's all, nothing!