Mr. Wang bought 20 dictionaries for 160 yuan. How much will it cost to buy another 30

If you want to buy another 30 copies, it's X
20:30=160:X
20X=30*160
X=240

Mr. Zhang bought a new English Chinese dictionary for his school as a prize for "three good students". He found that if he bought 30 copies, he still had 160 yuan left; if he bought 35 copies, he still had 20 yuan left. How much is each dictionary? How much money did Mr. Zhang bring?

160-20）÷（35-30），
=140÷5，
=28 yuan;
28 × 30 + 160 = 1000 yuan;
A: each dictionary is 28 yuan, and Mr. Zhang has 1000 yuan

I said to my mother, "this is a good thing I bought for you."

He told his mother that it was a good thing he had bought for her

Aunt Li bought 5 pears and 9 apples, a total of 3.3 grams. A pear weighs () kg? What about an apple?

Let a pear weigh a kilogram and an apple weigh B kilogram
Then: 5A + 9b = 3.32A = 3B
Replace 2A = 3B into 5A + 9b = 5A + 6A = 11a = 3.3
So a = 0.3 3B = 2A = 0.6
So B = 0.2
So a pear weighs 0.3 kg and an apple weighs 0.2 kg

Aunt Li bought 5 pears and 9 apples, a total of 3.3 kg. If the weight of 2 pears and 3 apples is equal, how many kilos does a pear and an apple weigh

Aunt Li from the fruit store brought some apples and pears. The weight ratio of apples to pears is 3:1. Apples are 120kg more than pears. How many kilograms are apples and pears in total?

Apple 120 × (3-1) × 3 = 180 kg
Pear 180-120 = 60 kg
180 + 60 = 240 kg

Aunt Li bought 5 pears and 9 apples, a total of 3.3 kg. If the weight of 2 pears and 3 apples, how many kg does a pear and an apple weigh? Don't use a quadratic equation of two variables, just let X!

If an apple weighs x kg, then a pear weighs 3x / 2kg
5×3x/2+9x=3.3
（7.5+9）x=3.3
16.5x=3.3
x=0.2
2 × 3 / 2 = 0.3 kg
A: an apple weighs 0.2kg, while a pear weighs 0.3KG

Three apples a pear weight 950 grams, an apple three pears a total of 1170 grams, an apple a pear how many kilograms each No equations

X = apple, y = pear
3x+y=950
x+3y=1170
y=950-3x
x+3*(950-3x)=1170
x+2850-9x=1170
8x=1680
x=210
y=320
It's a very simple equation with two variables

1. If you buy 30 kg of three kinds of fruits, you will get 80 yuan. Among them, 4 yuan per kilogram of apples, 3 yuan per kilogram of oranges, and 2 yuan per kilogram of pears There are several ways to buy

4 × Apple + 3 × orange + 2 × pear = 80
Apple + orange + pear = 30

A total of 30 kg of three kinds of fruits, with a total price of no more than 70 yuan, including 4 yuan per kilogram of apples, 3 yuan per kilogram of oranges, and 2 yuan per kilogram of raw pears Please fill in the price of 3 kg of fruit, which is 3 yuan for each kind of fruit!

28 kg pear, 1 kg apple and orange
27 pears, 2 apples and 1 orange
27 pears, 1 apple, 2 oranges
26 pears, 2 apples, oranges

Mr. Wang bought 20 dictionaries for 160 yuan. How much will it cost to buy another 30