Examples for 7th grade (seventh) - page 38

1. Digits of age The product of the digits of Andrew age as 6 years ago and not equal to 0. Andrew age is also the smallest possible age with this two conditions. After how many years will be the product of the digits of Andrew age again the same as today?
2. Cash back After a trip 24 students have left more than 650 but less than 690 CZK (Kc). How much each student receives return when the amount is divisible by the number of pupils?
3. 100 % How much is 100%, if 17 % is 1169?
4. Trapezium The area of trapezium is 35cm2 find its altitude if the bases are 6cm and 8cm.
5. Copper plate Calculate the thickness of the copper plate with a density 8.7 g/cm³ measuring 1.5 meters and 80 cm and its weight is 3.65 kg
6. Athletes Athletes standing in rows of eight. Ivan estimated that athletes are more than 120. Peter claimed that there are fewer than 130. Both are right. How many are athletes?
7. Harvester Harvester has cutting width 4 m and harvested grain in the field, which is 87 meters wide. Harvester moves along the length of the field for six minutes, going back (without cutting) it takes half the time. Each turn at the end field take one minute. How m
8. Tram stop At the tram stop met tram No. 4 and no. 5 at 10 AM. Tram no. 4 runs every 5 minutes, tram No. 5 at an interval of 7 minutes. How many times will meet until 12 o'clock?
9. Purchase Three buyers pay € 468. The first paid 3-times more than second, third half over second. How many euros paid each of them?
10. Third dimension Calculate the third dimension of the cuboid: a) V = 224 m3, a = 7 m, b = 4 m b) V = 216 dm3, a = 9 dm, c = 4 dm
11. Mother and daughter 2 The mother is 40 years older than her daughter. How old is the mother if her age is eight thirds age of daughter?
12. CD disc A compact disc has a diameter of 11.8 cm. What is the surface area of the disc in square centimeters?
13. VAT lottery Father earns 993 euro a month, mother 918 euro per month. Calculate what amount they paid as value added tax (VAT) to the government if the VAT rate is 20%. Assume that the family will spend their entire monthly income.
14. The ship The ship went upstream speed of 20 km/h in relation to water. River flows at speed 10 km/h. After half an hour, he stopped and returned downstream to the starting point. How long it took way back when even if downstream speed of ship is 20 km/h in relation
15. Efficiency A certain device consumes 28 kW and delivers 14 kW. Find its efficiency.
16. Hectoliters How many hectoliters of water fits into cuboid tank with dimensions of a = 3.5 m b = 2.5 m c = 1.4 m?
17. Tissues The store got three kinds of tissues - 132 children, 156 women and 204 men. Tissues each species were packed into boxes after the number of pieces the same for all three types (and greatest). Determine the number, if you know that every box has more than 6
18. Football season Throughout the football season gave Adam the 23 goals more than Brano and 16 goals less than Karol. Edo gave the 6 goals more Dušan. Karol gave 5 more than Edo. Brano and Edo gave together 17 goals. How many goals gave each boy and how many goals gave the.
19. Stamps and albums Michail has in three albums stored 170 stamps. In the first album, there are 14 more than in the second and in the second is by 1/5 less than in the third. How many stamps are in the first album?
20. Boots Master shoemaker has three apprentices. First do one pair of boots for two days, second for 1 day, third on 1.5 day. If they worked together, for how long it would take made a couple of boots?

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