# Units - examples - page 109

1. A man 2
A man divides \$10,000 into two investments, one at 10% and the other at 30%. Find how much is invested at each rate so that the two investments produce the same income annually.
2. A boy
A boy of height 1.7m is standing 30m away from flag staff on the same level ground . He observes that the angle of deviation of the top of flag staff is 30 degree. Calculate the height of flag staff.
3. Ophelia
Ophelia recorded the temperature of a cold store every two hours. 1. At 6am it was -4°C and at 8am it was -1°C. By how much did the temperature rise? 2. The temperature went up by 5°C in the next two hours. .What was the temperature at 10am?
4. Brick weight
Half the weight of a brick plus 20 pounds is equal to 1/3 the weight of the brick plus 30 pounds. How much does the brick weigh?
5. Two gears
The two gears fit together. The larger gear has 32 teeth, the smaller has 20 teeth less. How many times does turn a smaller gear if the bigger gear turns three times?
6. Area to volume
If the surface area of a cube is 486, find its volume.
7. A cylindrical tank
A cylindrical tank can hold 44 cubic meters of water. If the radius of the tank is 3.5 meters, how high is the tank?
8. Fe metal sheet
For one product, 5/8 of the metal sheet are consumed, to the second 5/6 of remains. What part of the sheet metal is consumed for both products together?
9. Bricklayer
How much do we pay for a bricklayer laying a pavement in a square room with a diagonal of 8 m, if 1 sqm with work will cost for CZK 420?
10. Free fall
The free fall body has gone 10m in the last 0.5s. Find the body speed at the moment of impact.
11. Ebay is not free
Be aware of ebay - if you sell something expensive, fee is painful. There are lot of space for classifieds and local exchange away from global ebay. Calculate ebay+paypal fee if you sale 3037 USD laptop. Formula for ebay fee is 0,30 + 10 % of total earning
12. Center of line segment
Calculate the distance of the point X [1,3] from the center of the line segment x = 2-6t, y = 1-4t ; t is .
13. Car overtaking
A passenger car travels at a speed of 30 m/s, and before it travels freight truck that drives at a constant speed of 10 m/s. Within 30 meters of the truck, the driver of the car finds out that the truck can not overtake. That's why it starts braking with a
14. Three friends
Cuba, Matthew and their friend Adam found a brigade during their weekend weekends because they wanted to make a joint trip to the Alps that they planned for the spring break. Cuba enjoyed the skiing trip very much, so he was not lazy to get up and went t
15. Ditch
Ditch profile is an isosceles trapezoid with bases of length 80m and 60m. The slope of the side wall of the ditch is 80°. Calculate the ditch depth.
16. Drying herbs
Herbs lose 75% weight By drying. How many fresh herbs do you have to collect if you want to make 1.5 kg of dried herbs?
17. T-shirts and hat
5 t-shirts and a hat cost £62.00 2 t-shirts and a hat cost £29.00 How much does a t-shirt cost ? How much does a hat cost ?
18. The garden
The garden has the shape of a rectangular trapezium. The bases have lengths of 27 meters and 36 meters, the trapezoid's height is 12 meters. Calculate how much fence will cost this garden if one meter costs 1.5 €?
19. Paper box
Calculate how much we'll pay for a three-side shaped prism box with a triangular base, and if it measures 12cm and 1.6dm, the hypotenuse measures 200mm. The box is 34cm high. We pay 0,13 € per square meter of paper.
20. Insect spraying
In 600 ml of spraying is 5 ml of an active ingredient. How much is it per miles?

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