Match the math sentence that count on and back by tens.

38+20=? 63+40=? 42+30=?

77-30=? 53-40=? 91-20=?

38+20 = thirty-eight, forty eight, fifty eight.

63+40 = sixty-three, seventy-three, eighty-three, ninety-three, one-hundred three

42+30=forty-two, fifty-two, sixty-two, seventy-two, eighty-two. 77-30 = Seventy-seven sixty-seven, fifty-seven, forty-seven 53-40=fifty-three, forty-three, thirty-three, twenty-three, thirteen

91-20 = Ninety-one, eighty-one, seventy-one

This method is where you count up and down by tens.