Multiple Problems
1. Simplify $4^{5a+3b} + 3(2a-b)$.
Step 1: Recognize $4^{5a+3b}$ is an exponential term that cannot be simplified further without values for $a$ and $b$.
Step 2: Expand the second part: $3(2a-b) = 6a - 3b$.
Final expression: $$4^{5a+3b} + 6a - 3b$$
2. The distance on the map between towns is 15 cm, scale is 1 cm = 20 km.
Calculate actual distance: $$15 \times 20 = 300$$ km.
3. Convert XLVI + XV to Hindu Arabic numerals.
XLVI = 40 + 6 = 46
XV = 10 + 5 = 15
Sum: $$46 + 15 = 61$$
4. Volume of cuboid with length=5 cm, width=4 cm, height=4 cm.
Volume formula: $$V = l \times w \times h$$
Compute: $$5 \times 4 \times 4 = 80$$ cm³.
5. Measure angle marked X with adjacent angles 76° and 67°.
If angle X is supplementary to sum of 76° and 67°, then
$$X = 180° - (76° + 67°) = 180° - 143° = 37°$$
6a. Draw bar graph and tally table for Abraham's subjects and marks: Kis(70), Eng(90), Maths(85), Sci(75), Socs(80), CRE(95), Music(80).
6b. Subjects with same marks: Socs(80) and Music(80).
6c. Total marks:
$$70 + 90 + 85 + 75 + 80 + 95 + 80 = 575$$
7. Area of shaded triangle with base=30 cm and height=12 cm.
Formula: $$\text{Area} = \frac{1}{2} \times \text{base} \times \text{height}$$
Compute: $$\frac{1}{2} \times 30 \times 12 = 180$$ cm².
8. Convert 23 kg 356 g to grams.
$$23\text{ kg} = 23000\text{ g}$$
Total grams: $$23000 + 356 = 23356$$ g.
9. Add fractions: $\frac{3}{2} + 5 \frac{3}{4}$.
Convert mixed number:
$$5 \frac{3}{4} = \frac{23}{4}$$
Rewrite $\frac{3}{2}$ as $\frac{6}{4}$
Sum:
$$\frac{6}{4} + \frac{23}{4} = \frac{29}{4} = 7 \frac{1}{4}$$
10. Perimeter of Andrew's plot with length=75 m and width=68 m.
Perimeter formula:
$$P = 2(l + w) = 2(75 + 68) = 2 \times 143 = 286$$ m.
11. Work out: $0.083 + 12.3 + 4.8$.
Sum:
$$0.083 + 12.3 = 12.383$$
$$12.383 + 4.8 = 17.183$$
12. Find the value of X given adjacent angles 76° and 67°.
Assuming X is the angle between them:
$$X = 180° - 76° - 67° = 37°$$
13. Subtract lengths:
$$15 \text{ km } 118 \text{ m } 5 \text{ cm} - 7 \text{ km } 200 \text{ m } 15 \text{ cm}$$
Convert:
15 km 118 m 5 cm = 15 km 118 m 5 cm
Subtract 7 km 200 m 15 cm
Borrow meters and centimeters:
Meters: 118 m - 200 m (borrow 1 km=1000 m), meters = 1118 m - 200 m = 918 m
Centimeters: 5 cm -15 cm (borrow 1 m=100 cm), centimeters = 105 cm - 15 cm = 90 cm
Kilometers: 15 km - 7 km - 1 km (borrowed) = 7 km
Result:
7 km 918 m 90 cm
14. Subtract 500 g from 3 1/4 kg.
Convert 3 1/4 kg to grams:
$$3.25 \text{ kg} = 3250 \text{ g}$$
Subtract:
$$3250 - 500 = 2750 \text{ g}$$
Or back to kg:
$$2.75 \text{ kg}$$
15. Solve for $m$: $3(2m + 2) = 48$.
Step 1: Expand left side:
$$6m + 6 = 48$$
Step 2: Subtract 6:
$$6m = 42$$
Step 3: Divide by 6:
$$m = 7$$
16. Josjam’s plot perimeter = 74 m, width = 14 m, find length.
Formula:
$$P = 2(l + w)$$
Solve for $l$:
$$74 = 2(l + 14)$$
$$37 = l + 14$$
$$l = 23$$ m
17. Multiply $14 \times 5 \frac{2}{7}$.
Convert mixed number:
$$5 \frac{2}{7} = \frac{37}{7}$$
Multiply:
$$14 \times \frac{37}{7} = 2 \times 37 = 74$$
18. In right-angled triangle ABC, with $\angle ACB = 90°$, $AB = 8$ cm, $AC = 5$ cm.
Find length $BC$ using Pythagoras theorem:
$$BC = \sqrt{AB^2 - AC^2} = \sqrt{8^2 - 5^2} = \sqrt{64 - 25} = \sqrt{39} \approx 6.24$$ cm.