# Algebra - math word problems

1. Acid The barrel is 199 litres of 38% acid. How many percent acid occurs when 61 litres revoke and replace it with the same amount of water?
2. Right triangle Calculate the missing side b and interior angles, perimeter and area of ​​a right triangle if a=10 cm and hypotenuse c = 16 cm.
3. Right triangle Legs of the right triangle are in the ratio a:b = 2:8. The hypotenuse has a length of 87 cm. Calculate the perimeter and area of the triangle.
4. The cyclist The cyclist went from village to town. First half of journey went at 20 km/h. The second half of the journey, which mostly fell, went at 39 km/h. All journey took 88 minutes. Calculate the distance from the village to the town.
5. Angles in triangle The triangle is ratio of the angles β:γ = 6:8. Angle α is 40° greater than β. What are the size of angles of the triangle?
6. Tourist Tourist walk at 4.1 km/h. Every 5 km have 20-minute break. How many kilometers passed, when started at 4:40 and finished at 10:30?
7. Raffle In the pool is numbers from 1 to 115. What is the probability that a randomly selected number is not a prime number?
8. Two numbers Find two numbers whose difference and ratio is 2.
9. Proof I When added to the product of two consecutive integers larger one, we get square larger one. Is this true or not? Passenger car and an ambulance come to the rectangular crossroad, the ambulance left. Passenger car at speed 39 km/h and ambulance at 41 km/h. Calculate such a relative speed of the ambulance move to the car. Solve quadratic equation: 2x2-58x+396=0
12. Exponential equation Solve exponential equation (in real numbers): 98x-2=9
13. Trapezoid Calculate area of trapezoid ABCD with sides |AD|= 68 cm, |DC|=35 cm, |CB|=12 cm, |AB|=35 cm..
14. Arc and segment Calculate the length of circular arc l, area of the circular arc S1 and area of circular segment S2. Radius of the circle is 33 and corresponding angle is ?.
15. Chestnuts Neil has 5-times chestnuts less than Adrian. Together they have 894 chestnuts. How many chestnuts has Neil and Adrian? After 548 hours decreases the activity of a radioactive substance to 1/9 of the initial value. What is the half-life of the substance?
17. Wind drift The plane flies at 860 km/h, passing distance 3000 kilometers with the wind and once again against the wind for 6 h 59 min. What is the wind speed?
18. Circle arc Circle segment has a circumference of 135.26 dm and 2096.58 dm2 area. Calculate the radius of the circle and size of central angle.
19. Rates When gas consumption, the consumer may choose one of two rates: rate A - which pays 0.4 € per 1 m3 of gas a flat monthly fee of 3.9 € (regardless of consumption) rate B - which pays 0.359 € per 1 m3 of gas a flat monthly fee of 12.5 € From what monthl
20. Geometric progression Fill 4 numbers between 4 and -12500 to form geometric progression.

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