L5 · Money and decimal notation: clinic
“I can read, write, compare, order, and round money amounts in decimal notation - dollars and cents - converting between cents and dollars and using place value to keep every digit honest.”
Write "two thousand four hundred six dollars and thirty-five cents" in decimal notation. Step 1 (dollars first): 2,406 dollars -> 2,406. Step 2 (cents become hundredths): 35 cents = 35 hundredths of a dollar -> .35. Step 3 (join): $2,406.35. Now the trap twin: 4 dollars and 7 cents is $4.07, NOT $4.7. Seven cents is 7 hundredths ($0.07); $4.7 is $4.70 - seventy cents. The zero in $4.07 is not decoration; it pushes the 7 into the hundredths place where cents live. Converting the other way: cents / 100 gives dollars - 1,250 cents = $12.50.
$4.07 and $4.70 differ because...
Write in decimal notation: 9 dollars and 3 cents -> $9.03
"850 cents = 850 / 100 = ___ dollars, written $___" -> 8.50
10 scored questions with a 3-rung hint ladder. Mastery needs 8/10 plus both gate questions.