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9. Once, Shreya’s grandmother was suffering from anemia because the hemoglobin level in her blood
was lower than the normal range. The doctor advised her to take one iron tablet twice a day. If the
cost of 10 tablet strips was `28, then what amount did she pay for her medical bill for 2 weeks?
10. A student said that the ratios 3 : 4 and 9 :16 were proportional. What error did the student make?

11. Online shopping has increased many folds in the last few years. There are many websites and
mobile applications that allows buyers to purchase goods online. In a week, on different days,
Sameer bought some items online which, are shown in the given table along with their price. CASE STUDY
S.No. Items Quantity Bought Price Per Item (`)

1. Cricket Bat 1 1750
2. Puzzle Book 1 875
3. Chocolate Bar 5 75

4. Pizza 2 375
Based on the above information, answer the following questions:

(a) What is the ratio of price of 1 cricket bat to that of 1 puzzle book?
(b) Is it possible to find the ratio between price of an item and its quantities bought?
(c) If x, y, z and w denoted the price of 1 cricket bat, 1 puzzle book, 5 chocolate bars and 2
pizzas. Verify whether y : x : : z : w is true.

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MAths connect

An alloy is a homogenous mixture of two or more metals or a metal and a non−metal in definite proportion.
For example: Stainless steel − It is a mixture of iron, nickel and chromium. Brass − It is a mixture of two metals
- copper and zinc.
Suppose an alloy of brass is produced by combining copper and zinc by weight in the ratio 2:3. How many kg
of copper is needed to produce 240 kg of the brass alloy?
Discuss with your science teacher to know more about the alloy metals and find five more alloys and write the
ratio of metals used in them.

Brain Sizzlers
A tower casts a shadow of length 100 m at the same time a 12 m high pole casts a shadow of length 16 m. Find
the height of the tower.

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