{
    "name": "Daily Bell Ringers Library",
    "description": "Free bell ringers (3–5 minute classroom warm-ups) for grades 6–12, with answers and teacher notes.",
    "url": "https://dailybellringers.org/bell-ringer-library/math/grades-9-12/",
    "license": "https://creativecommons.org/licenses/by-nc/4.0/",
    "credit": "Daily Bell Ringers (dailybellringers.org)",
    "filters": {
        "subject": "Math",
        "grade": "Grades 9–12"
    },
    "generated": "2026-10-14T18:03:03+00:00",
    "count": 3,
    "items": [
        {
            "id": 125,
            "date": "2026-10-14",
            "grade": "Grades 9–12",
            "subject": "Math",
            "topic": "Solving a ticket-sales system of equations",
            "prompt": "A theater sold 150 tickets for a play and collected $1,350. Adult tickets cost $12 and student tickets cost $7. Write a system of equations and solve it to find how many of each ticket were sold.",
            "answer": "Let a = adult tickets and s = student tickets.\na + s = 150\n12a + 7s = 1,350\nSubstitute s = 150 − a: 12a + 7(150 − a) = 1,350 → 12a + 1,050 − 7a = 1,350 → 5a = 300 → a = 60 adult tickets, so s = 90 student tickets.\nCheck: 60 + 90 = 150 tickets, and 60 × $12 + 90 × $7 = $720 + $630 = $1,350. Fast estimate for discussion: if all 150 were student tickets, the total would be $1,050; each adult ticket adds $5, and $300 ÷ $5 = 60 adults.",
            "sources": "",
            "url": "https://dailybellringers.org/bell-ringer/math-bell-ringer-grades-9-12-solving-a-ticket-sales-system-of-equations/",
            "set_url": "https://dailybellringers.org/bell-ringers-grades-9-12-2026-10-14/",
            "pin": "https://dailybellringers.org/wp-content/uploads/pins/lib-math-bell-ringer-grades-9-12-solving-a-ticket-sales-system-of-equations.png?v=b477f2d9"
        },
        {
            "id": 85,
            "date": "2026-10-13",
            "grade": "Grades 9–12",
            "subject": "Math",
            "topic": "Comparing two-dice probabilities",
            "prompt": "You roll two fair six-sided dice and add the numbers. Which is more likely: a sum of 7 or a sum of 10? Give the probability of each as a fraction in lowest terms.",
            "answer": "There are 6 × 6 = 36 equally likely outcomes.\nSum of 7: (1,6), (2,5), (3,4), (4,3), (5,2), (6,1) = 6 outcomes, so 6/36 = 1/6.\nSum of 10: (4,6), (5,5), (6,4) = 3 outcomes, so 3/36 = 1/12.\nA sum of 7 is twice as likely as a sum of 10. Check: 1/6 = 2/12. The most common error is counting (4,6) and (6,4) as the same outcome; on two separate dice they are different.",
            "sources": "",
            "url": "https://dailybellringers.org/bell-ringer/math-bell-ringer-grades-9-12-comparing-two-dice-probabilities/",
            "set_url": "https://dailybellringers.org/bell-ringers-grades-9-12-2026-10-13/",
            "pin": "https://dailybellringers.org/wp-content/uploads/pins/lib-math-bell-ringer-grades-9-12-comparing-two-dice-probabilities.png?v=324bea43"
        },
        {
            "id": 75,
            "date": "2026-10-12",
            "grade": "Grades 9–12",
            "subject": "Math",
            "topic": "Solving a linear equation",
            "prompt": "Solve for x, then check your answer: 3(x − 4) = 2x + 5",
            "answer": "3x − 12 = 2x + 5 → x − 12 = 5 → x = 17\nCheck: 3(17 − 4) = 3(13) = 39, and 2(17) + 5 = 39. Both sides match. The most common error is distributing the 3 to x only and writing 3x − 4.",
            "sources": "",
            "url": "https://dailybellringers.org/bell-ringer/math-bell-ringer-grades-9-12-solving-a-linear-equation/",
            "set_url": "https://dailybellringers.org/bell-ringers-grades-9-12-2026-10-12/",
            "pin": "https://dailybellringers.org/wp-content/uploads/pins/lib-math-bell-ringer-grades-9-12-solving-a-linear-equation.png?v=e6d89ed8"
        }
    ]
}