Word Problems

1, The units digit of a 2 digit number is 4 more than the tens digit. If the digits are reversed, the new number is 10 more than twice the original number. What is the number?

2.In a three digit number, twice the hundreds digit exceeds the sum of the tens and unit digits by 3. When the digits are reversed, the new number if 198 great er than the original number. The sum of the digits of the new number is 12. What is the original number?

3. The sum of the digits in a three digit number is 14. The tems digit exceeds twice the hundreds digit by one. If 3 were added to the number, the new number would be a palindrone (the same backwards as forwards.). Find the original number.

4.The sum of the digits of a two-digit number is 11. If we interchange the digits then the new number formed is 45 less than the original. Find the original number.

5. The unit's digit of a two digit number is twice its ten's digit. If 18 is added to the number, the digits interchange their places. Find the number.

6. It costs $140 to buy a cord of firewood, delivered to your house and $80 to buy 1/2 cord of firewood delivered to your house. Assuming that you pay a certain price for the wood and a fixed price for delivery, how much would it cost for 1.5 cords of wood to be delivered?

7. The tens digit of a two digit number is twice the units digit. If 36 is subtracted from the number the digits would be reversed. Find the original number

8. Solve this system of three variables

1/x - 2/y - 2/z = 1

3/x + 4/y + 6/z = -9

1/x + 2/y + 2/z = -5

9. Solve this system of three variables

2/x + 1/y - 1/z = 4.

3/x - 1/y + 2/z = 15

1/x - 3/y + 4/z = 13

10.Joe traveled against the wind in a small plane for 3.2 hr. The return trip with the wind took 2.8 hr. Find the speed of the wind if the speed of the plane is still air is 170 mph.