Page 29 - Start Up Mathematics_7

6. Write five pairs of integers (a, b) such that a ÷ b = –3. One such pair is (6, –2) because 6 ÷
(–2) = (–3).

7. The temperature at 12 noon was 10°C above zero. If it decreases at the rate of 2°C per hour
until midnight, at what time would the temperature be 8°C below zero? What would be the
temperature at mid-night?
Exemplar Problems

1. The next number in the pattern –62, –37, –12, ... is:
(a) 25 (b) 13 (c) 0 (d) –13
2. The value of 5 ÷ (–1) does not lie between:

(a) 0 and –10 (b) 0 and 10 (c) –4 and –15 (d) –6 and 6
3. When we divide a negative integer by a positive integer, we divide them as whole numbers
and put a _______ sign before quotient.
4. When we multiply two integers their product is always greater than both the integers.
(True/False)

5. Difference of two negative integers cannot be a positive integer. (True/False)
6. The Greco-Roman era, when Greece and Rome ruled Egypt started in the year 330 BC and
ended in the year 395 AD. How long did this era last? (While solving this problem take
1 BC as –1 and 1 AD as +1.)
7. Evaluate the following, using distributive property.
(a) 53 × (–9) – (–109) × 53 (b) 68 × (–17) + (– 68) × 3

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