Read Online Numbed! by David Lubar - Free Book Online Page A

looked over my shoulder. Ms. Fractalli was yanking at her new lock.
    â€œWhat’s wrong?” I asked.
    â€œI was afraid I’d lose the piece of paper with the instructions, the way I was always losing the key, so I put it in my purse,” she said. “Then I locked my purse in the cabinet, as I always do.”
    â€œYou didn’t memorize the combination?” I asked.
    She shrugged. “I didn’t get a chance to memorize it or even look at it. I was up pretty late grading the tests.”
    â€œLet me see.” I liked playing with locks.
    â€œIt’s hopeless,” she said. “There are too many combinations.”
    I lifted up the lock and looked at it. There were five buttons on front, labeled A, B, C, D, E. “How does it work?” I asked.
    â€œI’m supposed to push some of them in,” she said. “But I don’t know which ones or how many.”
    â€œI can get a saw,” Benedict said. “Yeah—a power saw. Or those giant pliers they use on cars. Wait! Better idea! We could go to the high school and get some hydrochloric acid from the chemistry lab. That will eat right through it.”
    He kept talking, but I stopped listening. The lock had all of my attention. I knew there were letters on it. But it reminded me of the kind of number problems we’d solved at the museum.
    â€œIt’s binary!” I shouted as the answer hit me.
    â€œCool,” Benedict said. He stopped talking and looked over my shoulder. “Yeah, you’re right.”
    I turned toward Ms. Fractalli. “If there was just one button, you’d only have two choices. Right?” I pushed down the button with A on it and then popped it back up.
    â€œAnd two buttons would only give you four choices,” Benedict said.
    â€œFor sure,” I said. It was definitely like the binary numbers we’d learned about. “And three buttons would be … ”
    â€œEight!” Benedict said. “Like Dr. Thagoras’s light switches.”
    I held up my right hand and stuck out one finger at a time, doubling the number with each new finger.
    Pinkie.
    â€œTwo.”
    Ring finger.
    â€œFour”
    Middle finger.
    â€œEight.”
    Benedict and Ms. Fractalli joined in.
    Index finger.
    â€œSixteen!”
    Thumb—my whole hand was spread wide.
    â€œThirty-two!”
    â€œThat’s not a lot at all,” Ms. Fractalli said. “I should have realized it right away.”
    â€œSometimes, we all forget our math skills,” I said. I thought about those pennies that doubled every week for a year. It’s a good thing the lock didn’t have fifty-two buttons. Or even ten.
    I started pushing the five buttons, going through the thirty-two possible combinations:
    up-up-up-up-up
    up-up-up-up-down
    up-up-up-down-up
    up-up-up-down-down
    up-up-down-up-up
    up-up-down-up-down
    up-up-down-down-up
    up-up-down-down-down
    I tugged on the lock after each combination. I hoped I wasn’t missing something. It seemed too easy. But then, after more than twenty attempts, I tried
    down-up-down-up-down.
    The lock pulled open.
    â€œI did it!” I shouted.
    â€œLogan, that was wonderful,” Ms. Fractalli said.
    I noticed that the A, C, and E were pushed down. “Ace,” I said. “I’ll bet you’ll never forget that combination.”
    â€œAnd I’ll never forget how you two helped me,” she said.
    â€œThat’s the power of two,” I said.
    She looked at the clock. “How’d you boys like another chance at the last part of the test?”
    If anyone had ever told me I’d be cheering at a chance to take a math test, I never would have believed it. But I was sure cheering then.
    â€œReady?” I asked Benedict as we walked back to our desks with new copies of the test.
    â€œLet’s ace this,” he said.
    â€œShhh,” I said. “That combination is a secret.”
    But when Ms.