EX1A MATH CLASS7 D

1. Find the value of

(i) Absolute Value

(a) $\mathrm{\mid }425\mathrm{\mid }=425$ (The absolute value of a positive number is the number itself.)

(b) $\mathrm{\mid }-618\mathrm{\mid }=618$ (The absolute value of a negative number is its positive counterpart.)

(c) $-|-873| = -873$
(First, find the absolute value of -873, which is 873, then apply the negative sign.)

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2. Ordering Numbers

(i) From smallest to greatest: $-10, -8, 2, 5, 9, 16$

(Arrange the numbers in ascending order.)

(ii) From greatest to smallest: $100, 0, -56, -181, -250, -300$

(Arrange the numbers in descending order.)

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3. Elevation Table

Location	Elevation (in m)
P	-205
Q	1200
R	-1800
S	250

(i) Farthest from sea level: R (-1800 m)
(The location with the largest absolute elevation value is farthest from sea level.)

(ii) Nearest to sea level: P (-205 m)
(The location with the smallest absolute elevation value is nearest to sea level.)

(iii) Order from greatest to least elevation: Q (1200 m), S (250 m), P (-205 m), R (-1800 m)
(Arrange the elevations in descending order.)

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4. Addition

(i) $145 + 1362 = 1507$
(Add the two positive numbers.)

(ii) $(-274) + (-2593) = -2867$
(Add the two negative numbers, which increases the magnitude of the negative result.)

(iii) $(-475) + 318 = -157$
(Subtract the smaller absolute value from the larger one and keep the sign of the larger absolute value.)

(iv) $620 + (-1008) = -388$
(Subtract the smaller absolute value from the larger one and keep the sign of the larger absolute value.)

(v) $1159 + (-1159) = 0$
(Adding a number and its opposite results in zero.)

(vi) $(-320) + 812 = 492$
(Subtract the smaller absolute value from the larger one and keep the sign of the larger absolute value.)

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5. Subtraction

(i) $432-128=304$
(Subtract the smaller number from the larger one.)

(ii) $(-108)-65=-173$
(Subtracting a positive number from a negative number increases the magnitude of the negative result.)

(iii) $(-728)-(-415)=-313$
(Subtracting a negative number is the same as adding its positive counterpart.)

(iv) $650-(-175)=825$
(Subtracting a negative number is the same as adding its positive counterpart.)

(v) $(-215)-687=-902$

(Subtracting a positive number from a negative number increases the magnitude of the negative result.)

(vi) $(-317)-(-500)=183$
(Subtracting a negative number is the same as adding its positive counterpart.)

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6. Simplification

(i) $-18+12-(-4)+(-16)=-18+12+4-16=-18$
(Combine like terms and simplify step-by-step.)

(ii) $378-(-14)-18+185=378+14-18+185=559$
(Convert subtraction of negative numbers to addition and simplify.)

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7. Ronak's Elevation

Initial elevation: 55 m
Changes:$412,-125,272,-343,490,-640,50$
Total change: $412 - 125 + 272 - 343 + 490 - 640 + 50 = 116$
Final elevation: $55+116=171$ m

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8. Mauna Loa's Elevation Difference

Summit: 4170 m
Base: -13000 m
Difference: $4170-(-13000)=17170$

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9. Elevator's Elevation Change

Initial: -12 m
Final: -100 m
Change: $-100-(-12)=-88$ m

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10. Essay Score (MCQ)

The expression that does not represent the final score is:
(c) $|40|+|-12|+|7|$
(This expression adds the absolute values, which does not represent the actual score calculation.)

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11. Temperature Change (MCQ)

Change: $-2-10=-{12}^{\circ }\mathrm{C}$
Answer: (b) $<br>$

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