# Three-digit

How many three-digit natural numbers do not have the number 7?

**Result****Leave us a comment of example and its solution (i.e. if it is still somewhat unclear...):**

**Showing 0 comments:**

**Be the first to comment!**

#### To solve this example are needed these knowledge from mathematics:

## Next similar examples:

- Tunnels

Mice had built an underground house consisting of chambers and tunnels: • each tunnel leading from the chamber to the chamber (none is blind) • from each chamber lead just three tunnels into three distinct chambers, • from each chamber mice can get to any - Three friends

The three friends spent 600 KC in a teahouse. Thomas paid twice as much as Paul. Paul a half less than Zdeněk. How many each paid? - Three days

During the three days sold in stationery 1490 workbooks. The first day sold about workbooks more than third day. The second day 190 workbooks sold less than third day. How many workbooks sold during each day? - PIN - codes

How many five-digit PIN - code can we create using the even numbers? - Basket of fruit

In six baskets, the seller has fruit. In individual baskets, there are only apples or just pears with the following number of fruits: 5,6,12,14,23 and 29. "If I sell this basket," the salesman thinks, "then I will have just as many apples as a pear." Which - Bridge cards

How many bridge hands are possible containing 4 spades,6 diamonds, 1 club, and 2 hearts? - Dinning room

How many different combinations can we choose if there are 3 soups, 5 kinds of main dish and 2 desserts in the dining room? - Logik game

Letter game Logik is a two player game, which has the following rules: 1. The first player thinks five-letter word in which no letter is not repeated. 2. The second player writes a five-letter word. 3. The first player answers two numbers - the first numbe - Mom and daughter

Mother is 39 years old. Her daughter is 15 years. For many years will mother be four times older than the daughter? - Test points

If you earned 80% of the possible 40 points, how many points did you miss to get 100%? - Two numbers

We have two numbers. Their sum is 140. One-fifth of the first number is equal to half the second number. Determine those unknown numbers. - In the orchard

In the orchard, they planted 25 apple trees, 20 pears, 15 plums and 40 marbles. A strong late frost, however, destroyed a fifth of all new trees. Unfortunately, it was all the trees of one kind of fruit. What is the probability that the plums have died out - Walnuts

x walnuts were in the mission. Dano took 1/4 of nuts Michael took 1/8 from the rest and John took 34 nuts. It stayed here 29 nuts. Determine the original number of nuts. - Fifth of the number

The fifth of the number is by 24 less than that number. What is the number? - Tricolors

From the colors - red, blue, green, black and white, create all possible tricolors. - Liters od milk

The cylinder-shaped container contains 80 liters of milk. Milk level is 45 cm. How much milk will in the container, if level raise to height 72 cm? - Equations

Solve following system of equations: 6(x+7)+4(y-5)=12 2(x+y)-3(-2x+4y)=-44