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How Quantities Combine: Understanding Data

Each subtopic includes About section, revision page link, 10 preview questions, and practice CTAs.

Combining Things

Subtopic

Combining Things under How Quantities Combine: Understanding Data for Grade 9 CBSE.

About Topic & Revision

Preview questions (no answers)

  1. 1.

    An assembly line worker produces 100100 units per hour during their regular 88-hour shift. During 22 hours of overtime, they produce 150150 units per hour. What is their average production rate per hour over the full 1010 hours?

    A.

    125125 units/h

    B.

    115115 units/h

    C.

    110110 units/h

    D.

    120120 units/h

  2. 2.

    A shop inventory includes 55 watches with an average price of Rs 20002000 and 1515 clocks with an average price of Rs 400400. What is the average price of an item in this inventory?

    A.

    Rs 800800

    B.

    Rs 12001200

    C.

    Rs 600600

    D.

    Rs 10001000

  3. 3.

    A student mixes 11 L of a 5%5\% sugar solution with 99 L of pure water (0%0\% sugar). What is the sugar concentration of the resulting 1010 L mixture?

    A.

    1%1\%

    B.

    0.5%0.5\%

    C.

    2.5%2.5\%

    D.

    1.5%1.5\%

Download the worksheet for How Quantities Combine: Understanding Data - Combining Things to practice offline. It includes additional chapter-level practice questions.

Average of Averages

Subtopic

Average of Averages under How Quantities Combine: Understanding Data for Grade 9 CBSE.

About Topic & Revision

Preview questions (no answers)

  1. 1.

    A coffee blend is made by mixing 300300 g of beans costing Rs 22 per gram with 700700 g of beans costing Rs 11 per gram. What is the average cost per gram of the blend?

    A.

    Rs 1.51.5

    B.

    Rs 1.31.3

    C.

    Rs 1.71.7

    D.

    Rs 1.21.2

  2. 2.

    A software tester finds an average of 33 bugs per day during the first 55 days of a project and an average of 88 bugs per day during the next 55 days. What is the combined average bugs found per day?

    A.

    5.55.5

    B.

    55

    C.

    66

    D.

    4.54.5

  3. 3.

    A group of 44 seniors have an average age of 1818 years. A group of 66 juniors have an average age of 1313 years. What is the sum of the ages of all 1010 students?

    A.

    150150 years

    B.

    130130 years

    C.

    7272 years

    D.

    7878 years

Download the worksheet for How Quantities Combine: Understanding Data - Average of Averages to practice offline. It includes additional chapter-level practice questions.

Mixtures

Subtopic

Mixtures under How Quantities Combine: Understanding Data for Grade 9 CBSE.

About Topic & Revision

Preview questions (no answers)

  1. 1.

    Two equal quantities of juice are mixed. Batch A has 14%14\% sugar and Batch B has 22%22\% sugar. What is the resulting sugar percentage?

    A.

    16%16\%

    B.

    18%18\%

    C.

    20%20\%

    D.

    21%21\%

  2. 2.

    A 1 litre1\text{ litre} solution of 8%8\% salt is mixed with 3 litres3\text{ litres} of 12%12\% salt solution. Find the final concentration.

    A.

    10%10\%

    B.

    11%11\%

    C.

    11.5%11.5\%

    D.

    12%12\%

  3. 3.

    An alloy contains 300 g300\text{ g} of copper at 60%60\% purity and 700 g700\text{ g} of copper at 90%90\% purity. Find the final purity percentage of the copper alloy.

    A.

    75%75\%

    B.

    81%81\%

    C.

    83%83\%

    D.

    85%85\%

Download the worksheet for How Quantities Combine: Understanding Data - Mixtures to practice offline. It includes additional chapter-level practice questions.

Custom Weights

Subtopic

Custom Weights under How Quantities Combine: Understanding Data for Grade 9 CBSE.

About Topic & Revision

Preview questions (no answers)

  1. 1.

    If a dataset has two scores, 1010 and 2020, and the weighted average is 1818, find the ratio of the weights w1:w2w_1:w_2 for these scores.

    A.

    1:41:4

    B.

    1:21:2

    C.

    2:32:3

    D.

    1:51:5

  2. 2.

    A stock portfolio has two investments with weights 0.250.25 and 0.750.75. If the returns were 12%12\% and 4%4\% respectively, find the weighted average return.

    A.

    8%8\%

    B.

    6%6\%

    C.

    7%7\%

    D.

    5%5\%

  3. 3.

    A student’s overall grade is determined by Practical (weight 30%30\%) and Theory (weight 70%70\%). If the student scores 100100 in Practical and 6060 in Theory, calculate the total percentage.

    A.

    75%75\%

    B.

    80%80\%

    C.

    72%72\%

    D.

    68%68\%

Download the worksheet for How Quantities Combine: Understanding Data - Custom Weights to practice offline. It includes additional chapter-level practice questions.

Visualising and Interpreting Data

Subtopic

Visualising and Interpreting Data under How Quantities Combine: Understanding Data for Grade 9 CBSE.

About Topic & Revision

Preview questions (no answers)

  1. 1.

    In the provided geometry scene, if the circle represents total production (3600 units), how many units does the 60∘60^\circ sector represent?

    A.

    300300

    B.

    600600

    C.

    900900

    D.

    12001200

  2. 2.

    If the mean of 10 observations is 20, and each observation is multiplied by 3, what is the new mean?

    A.

    2020

    B.

    2323

    C.

    6060

    D.

    200200

  3. 3.

    Identify the mode from the following frequency table visualized as dots.

    A.

    22

    B.

    33

    C.

    44

    D.

    55

Download the worksheet for How Quantities Combine: Understanding Data - Visualising and Interpreting Data to practice offline. It includes additional chapter-level practice questions.

Stacking Columns

Subtopic

Stacking Columns under How Quantities Combine: Understanding Data for Grade 9 CBSE.

About Topic & Revision

Preview questions (no answers)

  1. 1.

    A savings chart shows contributions from 'Self' and 'Employer'. If 'Self' contributes Rs 4000Rs\ 4000 and 'Employer' contributes Rs 2000Rs\ 2000, identify the total height of the stacked bar.

    A.

    Rs 2000Rs\ 2000

    B.

    Rs 4000Rs\ 4000

    C.

    Rs 6000Rs\ 6000

    D.

    Rs 8000Rs\ 8000

  2. 2.

    A tower is built with two types of blocks: Red (bottom) and Blue (top). If the Red block is 1515 units high and the total tower height is 4040 units, what is the height of the Blue block?

    A.

    1515 units

    B.

    2525 units

    C.

    4040 units

    D.

    5555 units

  3. 3.

    In a stacked column chart representing 2424 hours of a day, the Sleep segment is 88 hours and the School segment is 66 hours. If these are the only two segments shown so far from the bottom, what is the yy-coordinate of the top of the School segment?

    A.

    66

    B.

    88

    C.

    1414

    D.

    2424

Download the worksheet for How Quantities Combine: Understanding Data - Stacking Columns to practice offline. It includes additional chapter-level practice questions.

An Alternative to Pie Chart

Subtopic

An Alternative to Pie Chart under How Quantities Combine: Understanding Data for Grade 9 CBSE.

About Topic & Revision

Preview questions (no answers)

  1. 1.

    In a multi-set bar graph, the height of Bar 1 is xx and Bar 2 is 2x2x. If x=15x=15, what is the combined height of both bars?

    A.

    30

    B.

    45

    C.

    15

    D.

    60

  2. 2.

    If two squares of area 1616 cm2cm^2 and 99 cm2cm^2 are placed side-by-side to form a composite shape, what is the total area of the shape?

    A.

    7 cm2cm^2

    B.

    25 cm2cm^2

    C.

    144 cm2cm^2

    D.

    12.5 cm2cm^2

  3. 3.

    A line segment AB is divided into two parts by point C. If AC = 4 cm and CB = 6 cm, what is the length of AB?

    A.

    2 cm

    B.

    24 cm

    C.

    10 cm

    D.

    8 cm

Download the worksheet for How Quantities Combine: Understanding Data - An Alternative to Pie Chart to practice offline. It includes additional chapter-level practice questions.